diff --git a/include/xlnt/serialization/style_serializer.hpp b/include/xlnt/serialization/style_serializer.hpp
index 988f2e47..5da0b181 100644
--- a/include/xlnt/serialization/style_serializer.hpp
+++ b/include/xlnt/serialization/style_serializer.hpp
@@ -37,6 +37,7 @@ class alignment;
 class border;
 class cell_style;
 class color;
+class common_style;
 class conditional_format;
 class fill;
 class font;
@@ -231,7 +232,7 @@ public:
     /// </summary>
     bool write_number_formats(xml_node &number_formats_node) const;
 
-    bool write_style_common(const alignment &style_alignment, const border &style_border, const fill &style_fill, const font &style_font, const number_format &style_number_format, const protection &style_protection, xml_node xf_node) const;
+    bool write_style_common(const common_style &style, xml_node xf_node) const;
 
     /// <summary>
     /// Build an xml tree representing the given style into style_node.
diff --git a/include/xlnt/styles/alignment.hpp b/include/xlnt/styles/alignment.hpp
index bb48690b..03289da3 100644
--- a/include/xlnt/styles/alignment.hpp
+++ b/include/xlnt/styles/alignment.hpp
@@ -56,15 +56,11 @@ public:
     void set_shrink_to_fit(bool shrink_to_fit);
     
     bool get_shrink_to_fit() const;
-    
-    void apply(bool value);
-    bool apply() const;
 
 protected:
     std::string to_hash_string() const override;
 
 private:
-    bool apply_ = false;
     horizontal_alignment horizontal_ = horizontal_alignment::none;
     vertical_alignment vertical_ = vertical_alignment::none;
     int text_rotation_ = 0;
diff --git a/include/xlnt/styles/border.hpp b/include/xlnt/styles/border.hpp
index 51df0cb0..d8679c7f 100644
--- a/include/xlnt/styles/border.hpp
+++ b/include/xlnt/styles/border.hpp
@@ -60,16 +60,11 @@ public:
     const std::experimental::optional<side> &get_vertical() const;
     std::experimental::optional<side> &get_horizontal();
     const std::experimental::optional<side> &get_horizontal() const;
-    
-    void apply(bool value);
-    bool apply() const;
 
 protected:
     std::string to_hash_string() const override;
 
 private:
-    bool apply_ = false;
-    
     std::experimental::optional<side> start_;
     std::experimental::optional<side> end_;
     std::experimental::optional<side> left_;
diff --git a/include/xlnt/styles/common_style.hpp b/include/xlnt/styles/common_style.hpp
index a58be223..26837089 100644
--- a/include/xlnt/styles/common_style.hpp
+++ b/include/xlnt/styles/common_style.hpp
@@ -53,36 +53,48 @@ public:
     const alignment &get_alignment() const;
     void set_alignment(const alignment &new_alignment);
     void remove_alignment();
+    bool alignment_applied() const;
+    void alignment_applied(bool applied);
     
     // Border
     border &get_border();
     const border &get_border() const;
     void set_border(const border &new_border);
     void remove_border();
+    bool border_applied() const;
+    void border_applied(bool applied);
     
     // Fill
     fill &get_fill();
     const fill &get_fill() const;
     void set_fill(const fill &new_fill);
     void remove_fill();
+    bool fill_applied() const;
+    void fill_applied(bool applied);
     
     // Font
     font &get_font();
     const font &get_font() const;
     void set_font(const font &new_font);
     void remove_font();
+    bool font_applied() const;
+    void font_applied(bool applied);
     
     // Number Format
     number_format &get_number_format();
     const number_format &get_number_format() const;
     void set_number_format(const number_format &new_number_format);
     void remove_number_format();
+    bool number_format_applied() const;
+    void number_format_applied(bool applied);
     
     // Protection
     protection &get_protection();
     const protection &get_protection() const;
     void set_protection(const protection &new_protection);
     void remove_protection();
+    bool protection_applied() const;
+    void protection_applied(bool applied);
     
 protected:
     std::string to_hash_string() const override;
@@ -93,6 +105,13 @@ protected:
     font font_;
     number_format number_format_;
     protection protection_;
+    
+    bool apply_alignment_;
+    bool apply_border_;
+    bool apply_fill_;
+    bool apply_font_;
+    bool apply_number_format_;
+    bool apply_protection_;
 };
 
 } // namespace xlnt
diff --git a/include/xlnt/styles/fill.hpp b/include/xlnt/styles/fill.hpp
index 1b743cd9..fa599875 100644
--- a/include/xlnt/styles/fill.hpp
+++ b/include/xlnt/styles/fill.hpp
@@ -117,16 +117,11 @@ public:
     double get_gradient_top() const;
 
     double get_gradient_bottom() const;
-    
-    void apply(bool value);
-    bool apply() const;
 
 protected:
     std::string to_hash_string() const override;
 
 private:
-    bool apply_ = false;
-    
     type type_ = type::none;
     pattern_type pattern_type_;
     gradient_type gradient_type_;
diff --git a/include/xlnt/styles/font.hpp b/include/xlnt/styles/font.hpp
index 83deda5d..d0658894 100644
--- a/include/xlnt/styles/font.hpp
+++ b/include/xlnt/styles/font.hpp
@@ -87,17 +87,12 @@ public:
     std::size_t get_family() const;
 
     bool has_scheme() const;
-    
-    void apply(bool value);
-    bool apply() const;
 
 protected:
     std::string to_hash_string() const override;
 
 private:
     friend class style;
-    
-    bool apply_ = false;
 
     std::string name_ = "Calibri";
     std::size_t size_ = 11;
diff --git a/include/xlnt/styles/number_format.hpp b/include/xlnt/styles/number_format.hpp
index 83be1c80..19c392e9 100644
--- a/include/xlnt/styles/number_format.hpp
+++ b/include/xlnt/styles/number_format.hpp
@@ -95,15 +95,11 @@ public:
     std::string format(long double number, calendar base_date) const;
 
     bool is_date_format() const;
-    
-    void apply(bool value);
-    bool apply() const;
 
 protected:
     std::string to_hash_string() const override;
 
 private:
-    bool apply_ = false;
     bool id_set_;
     std::size_t id_;
     std::string format_string_;
diff --git a/include/xlnt/styles/protection.hpp b/include/xlnt/styles/protection.hpp
index 450b9e6c..c89f4193 100644
--- a/include/xlnt/styles/protection.hpp
+++ b/include/xlnt/styles/protection.hpp
@@ -48,15 +48,11 @@ public:
 
     void set_locked(type locked_type);
     void set_hidden(type hidden_type);
-    
-    void apply(bool value);
-    bool apply() const;
 
 protected:
     std::string to_hash_string() const override;
 
 private:
-    bool apply_ = false;
     type locked_;
     type hidden_;
 };
diff --git a/include/xlnt/workbook/workbook.hpp b/include/xlnt/workbook/workbook.hpp
index 6dc7d179..e9cf7bd2 100644
--- a/include/xlnt/workbook/workbook.hpp
+++ b/include/xlnt/workbook/workbook.hpp
@@ -186,6 +186,7 @@ public:
     cell_style &get_style(std::size_t style_index);
     const cell_style &get_style(std::size_t style_index) const;
     std::size_t add_style(const cell_style &style);
+    void clear_styles();
     
     // Named Styles
     bool has_named_style(const std::string &name);
diff --git a/source/cell/cell.cpp b/source/cell/cell.cpp
index 9ab62df1..2537bae5 100644
--- a/source/cell/cell.cpp
+++ b/source/cell/cell.cpp
@@ -876,49 +876,49 @@ XLNT_FUNCTION timedelta cell::get_value() const
 void cell::set_border(const xlnt::border &border_)
 {
     d_->has_style_ = true;
-    auto style_copy = get_parent().get_parent().get_style(d_->style_id_);
+    auto style_copy = get_workbook().get_style(d_->style_id_);
     style_copy.set_border(border_);
-    d_->style_id_ = get_parent().get_parent().add_style(style_copy);
+    d_->style_id_ = get_workbook().add_style(style_copy);
 }
 
 void cell::set_fill(const xlnt::fill &fill_)
 {
     d_->has_style_ = true;
-    auto style_copy = get_parent().get_parent().get_style(d_->style_id_);
+    auto style_copy = get_workbook().get_style(d_->style_id_);
     style_copy.set_fill(fill_);
-    d_->style_id_ = get_parent().get_parent().add_style(style_copy);
+    d_->style_id_ = get_workbook().add_style(style_copy);
 }
 
 void cell::set_font(const font &font_)
 {
     d_->has_style_ = true;
-    auto style_copy = get_parent().get_parent().get_style(d_->style_id_);
+    auto style_copy = get_workbook().get_style(d_->style_id_);
     style_copy.set_font(font_);
-    d_->style_id_ = get_parent().get_parent().add_style(style_copy);
+    d_->style_id_ = get_workbook().add_style(style_copy);
 }
 
 void cell::set_number_format(const number_format &number_format_)
 {
     d_->has_style_ = true;
-    auto style_copy = get_parent().get_parent().get_style(d_->style_id_);
+    auto style_copy = get_workbook().get_style(d_->style_id_);
     style_copy.set_number_format(number_format_);
-    d_->style_id_ = get_parent().get_parent().add_style(style_copy);
+    d_->style_id_ = get_workbook().add_style(style_copy);
 }
 
 void cell::set_alignment(const xlnt::alignment &alignment_)
 {
     d_->has_style_ = true;
-    auto style_copy = get_parent().get_parent().get_style(d_->style_id_);
+    auto style_copy = get_workbook().get_style(d_->style_id_);
     style_copy.set_alignment(alignment_);
-    d_->style_id_ = get_parent().get_parent().add_style(style_copy);
+    d_->style_id_ = get_workbook().add_style(style_copy);
 }
 
 void cell::set_protection(const xlnt::protection &protection_)
 {
     d_->has_style_ = true;
-    auto style_copy = get_parent().get_parent().get_style(d_->style_id_);
+    auto style_copy = get_workbook().get_style(d_->style_id_);
     style_copy.set_protection(protection_);
-    d_->style_id_ = get_parent().get_parent().add_style(style_copy);
+    d_->style_id_ = get_workbook().add_style(style_copy);
 }
 
 template <>
@@ -955,7 +955,7 @@ std::string cell::to_string() const
 
 cell_style &cell::get_style()
 {
-    return get_parent().get_parent().get_style(d_->style_id_);
+    return get_workbook().get_style(d_->style_id_);
 }
 
 bool cell::has_style() const
@@ -965,7 +965,7 @@ bool cell::has_style() const
 
 void cell::set_style(const cell_style &style)
 {
-    d_->style_id_ = get_parent().get_parent().add_style(style);
+    d_->style_id_ = get_workbook().add_style(style);
     d_->has_style_ = true;
 }
 
diff --git a/source/cell/tests/test_cell.hpp b/source/cell/tests/test_cell.hpp
index 8b9c990d..a63cf1ab 100644
--- a/source/cell/tests/test_cell.hpp
+++ b/source/cell/tests/test_cell.hpp
@@ -10,6 +10,7 @@
 #include <xlnt/serialization/encoding.hpp>
 #include <xlnt/styles/alignment.hpp>
 #include <xlnt/styles/border.hpp>
+#include <xlnt/styles/cell_style.hpp>
 #include <xlnt/styles/font.hpp>
 #include <xlnt/styles/fill.hpp>
 #include <xlnt/styles/number_format.hpp>
@@ -367,7 +368,7 @@ public:
         cell.set_font(font);
         
         TS_ASSERT(cell.has_style());
-        TS_ASSERT(cell.get_font().apply());
+        TS_ASSERT(cell.get_style().font_applied());
         TS_ASSERT_EQUALS(cell.get_font(), font);
     }
     
@@ -383,7 +384,7 @@ public:
         cell.set_fill(f);
         
         TS_ASSERT(cell.has_style());
-        TS_ASSERT(cell.get_fill().apply());
+        TS_ASSERT(cell.get_style().fill_applied());
         TS_ASSERT_EQUALS(cell.get_fill(), f);
     }
     
@@ -397,7 +398,7 @@ public:
         cell.set_border(border);
         
         TS_ASSERT(cell.has_style());
-        TS_ASSERT(cell.get_border().apply());
+        TS_ASSERT(cell.get_style().border_applied());
         TS_ASSERT_EQUALS(cell.get_border(), border);
     }
     
@@ -410,7 +411,7 @@ public:
         cell.set_number_format(format);
         
         TS_ASSERT(cell.has_style());
-        TS_ASSERT(cell.get_number_format().apply());
+        TS_ASSERT(cell.get_style().number_format_applied());
         TS_ASSERT_EQUALS(cell.get_number_format().get_format_string(), "dd--hh--mm");
     }
     
@@ -425,7 +426,7 @@ public:
         cell.set_alignment(align);
         
         TS_ASSERT(cell.has_style());
-        TS_ASSERT(cell.get_alignment().apply());
+        TS_ASSERT(cell.get_style().alignment_applied());
         TS_ASSERT_EQUALS(cell.get_alignment(), align);
     }
     
@@ -440,7 +441,7 @@ public:
         cell.set_protection(prot);
         
         TS_ASSERT(cell.has_style());
-        TS_ASSERT(cell.get_protection().apply());
+        TS_ASSERT(cell.get_style().protection_applied());
         TS_ASSERT_EQUALS(cell.get_protection(), prot);
     }
 };
diff --git a/source/cell/text.cpp b/source/cell/text.cpp
new file mode 100644
index 00000000..da62331d
--- /dev/null
+++ b/source/cell/text.cpp
@@ -0,0 +1,62 @@
+// Copyright (c) 2014-2016 Thomas Fussell
+// Copyright (c) 2010-2015 openpyxl
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, WRISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE
+//
+// @license: http://www.opensource.org/licenses/mit-license.php
+// @author: see AUTHORS file
+
+#include <xlnt/cell/text.hpp>
+#include <xlnt/cell/text_run.hpp>
+
+namespace xlnt {
+
+void text::clear()
+{
+	runs_.clear();
+}
+
+void text::set_plain_string(const std::string &s)
+{
+	clear();
+	add_run(text_run(s));
+}
+
+std::string text::get_plain_string() const
+{
+	std::string plain_string;
+
+	for (const auto &run : runs_)
+	{
+		plain_string.append(run.get_string());
+	}
+
+	return plain_string;
+}
+std::vector<text_run> text::get_runs()
+{
+	return runs_;
+}
+
+void text::add_run(const text_run &t)
+{
+	runs_.push_back(t);
+}
+
+} // namespace xlnt
diff --git a/source/cell/text_run.cpp b/source/cell/text_run.cpp
new file mode 100644
index 00000000..05c5ccf0
--- /dev/null
+++ b/source/cell/text_run.cpp
@@ -0,0 +1,46 @@
+// Copyright (c) 2014-2016 Thomas Fussell
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, WRISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE
+//
+// @license: http://www.opensource.org/licenses/mit-license.php
+// @author: see AUTHORS file
+
+#include <xlnt/cell/text_run.hpp>
+
+namespace xlnt {
+
+text_run::text_run() : text_run("")
+{
+}
+
+text_run::text_run(const std::string &string) : string_(string)
+{
+}
+
+std::string text_run::get_string() const
+{
+	return string_;
+}
+
+void text_run::set_string(const std::string &string)
+{
+	string_ = string;
+}
+
+} // namespace xlnt
diff --git a/source/serialization/style_serializer.cpp b/source/serialization/style_serializer.cpp
index e3fa3383..96cd5385 100644
--- a/source/serialization/style_serializer.cpp
+++ b/source/serialization/style_serializer.cpp
@@ -31,6 +31,7 @@
 #include <xlnt/styles/alignment.hpp>
 #include <xlnt/styles/border.hpp>
 #include <xlnt/styles/cell_style.hpp>
+#include <xlnt/styles/common_style.hpp>
 #include <xlnt/styles/fill.hpp>
 #include <xlnt/styles/font.hpp>
 #include <xlnt/styles/named_style.hpp>
@@ -39,6 +40,7 @@
 #include <xlnt/workbook/worksheet_iterator.hpp>
 #include <xlnt/worksheet/cell_iterator.hpp>
 #include <xlnt/worksheet/cell_vector.hpp>
+#include <xlnt/worksheet/range.hpp>
 #include <xlnt/worksheet/worksheet.hpp>
 #include <xlnt/worksheet/range_iterator.hpp>
 
@@ -64,7 +66,7 @@ bool equals_case_insensitive(const std::string &left, const std::string &right)
 
 bool is_true(const std::string &bool_string)
 {
-    return bool_string == "1";
+    return bool_string == "1" || bool_string == "true";
 }
 
 xlnt::protection::type protection_type_from_string(const std::string &type_string)
@@ -187,6 +189,26 @@ namespace xlnt {
 
 style_serializer::style_serializer(workbook &wb) : workbook_(wb)
 {
+    std::unordered_set<number_format, std::hash<xlnt::hashable>> number_format_set;
+    
+    for (auto ws : workbook_)
+    {
+        for (auto row : ws.rows())
+        {
+            for (auto cell : row)
+            {
+                if (cell.has_style())
+                {
+                    number_format_set.insert(cell.get_number_format());
+                }
+            }
+        }
+    }
+    
+    for (auto nf : number_format_set)
+    {
+        number_formats_.push_back(nf);
+    }
 }
 
 protection style_serializer::read_protection(const xml_node &protection_node)
@@ -278,31 +300,30 @@ cell_style style_serializer::read_cell_style(const xml_node &style_node)
     cell_style s;
     
     // Alignment
-    s.get_alignment().apply(style_node.has_child("alignment") || is_true(style_node.get_attribute("applyAlignment")));
+    s.alignment_applied(style_node.has_child("alignment") || is_true(style_node.get_attribute("applyAlignment")));
 
-    if (s.get_alignment().apply())
+    if (s.alignment_applied())
     {
         auto inline_alignment = read_alignment(style_node.get_child("alignment"));
         s.set_alignment(inline_alignment);
     }
     
     // Border
-    s.get_border().apply(is_true(style_node.get_attribute("applyBorder")));
     auto border_index = style_node.has_attribute("borderId") ? std::stoull(style_node.get_attribute("borderId")) : 0;
     s.set_border(borders_.at(border_index));
+    s.border_applied(is_true(style_node.get_attribute("applyBorder")));
     
     // Fill
-    s.get_fill().apply(is_true(style_node.get_attribute("applyFill")));
     auto fill_index = style_node.has_attribute("fillId") ? std::stoull(style_node.get_attribute("fillId")) : 0;
     s.set_fill(fills_.at(fill_index));
+    s.fill_applied(is_true(style_node.get_attribute("applyFill")));
     
     // Font
-    s.get_font().apply(is_true(style_node.get_attribute("applyFont")));
     auto font_index = style_node.has_attribute("fontId") ? std::stoull(style_node.get_attribute("fontId")) : 0;
     s.set_font(fonts_.at(font_index));
+    s.font_applied(is_true(style_node.get_attribute("applyFont")));
 
     // Number Format
-    s.get_number_format().apply(is_true(style_node.get_attribute("applyNumberFormat")));
     auto number_format_id = std::stoull(style_node.get_attribute("numFmtId"));
 
     bool builtin_format = true;
@@ -321,11 +342,13 @@ cell_style style_serializer::read_cell_style(const xml_node &style_node)
     {
         s.set_number_format(number_format::from_builtin_id(number_format_id));
     }
+    
+    s.number_format_applied(is_true(style_node.get_attribute("applyNumberFormat")));
 
     // Protection
-    s.get_protection().apply(style_node.has_attribute("protection") || is_true(style_node.get_attribute("applyProtection")));
+    s.protection_applied(style_node.has_attribute("protection") || is_true(style_node.get_attribute("applyProtection")));
 
-    if (s.get_protection().apply())
+    if (s.protection_applied())
     {
         auto inline_protection = read_protection(style_node.get_child("protection"));
         s.set_protection(inline_protection);
@@ -348,17 +371,17 @@ named_style style_serializer::read_named_style(const xml_node &named_style_node,
     
     //TODO shouldn't have to set apply after set_X()
     s.set_alignment(base_style.get_alignment());
-    s.get_alignment().apply(base_style.get_alignment().apply());
+    s.alignment_applied(base_style.alignment_applied());
     s.set_border(base_style.get_border());
-    s.get_border().apply(base_style.get_border().apply());
+    s.border_applied(base_style.border_applied());
     s.set_fill(base_style.get_fill());
-    s.get_fill().apply(base_style.get_fill().apply());
+    s.fill_applied(base_style.fill_applied());
     s.set_font(base_style.get_font());
-    s.get_font().apply(base_style.get_font().apply());
+    s.font_applied(base_style.font_applied());
     s.set_number_format(base_style.get_number_format());
-    s.get_number_format().apply(base_style.get_number_format().apply());
+    s.number_format_applied(base_style.number_format_applied());
     s.set_protection(base_style.get_protection());
-    s.get_protection().apply(base_style.get_protection().apply());
+    s.protection_applied(base_style.protection_applied());
     
     return s;
 }
@@ -380,6 +403,11 @@ bool style_serializer::read_stylesheet(const xml_document &xml)
         workbook_.create_named_style(ns.second.get_name()) = ns.second;
     }
     
+    if (!cell_styles_.empty())
+    {
+        workbook_.clear_styles();
+    }
+    
     for (const auto &s : cell_styles_)
     {
         workbook_.add_style(s);
@@ -752,6 +780,11 @@ void style_serializer::initialize_vectors()
     {
         fonts_.push_back(font());
     }
+    
+    if (number_formats_.empty())
+    {
+        number_formats_.push_back(number_format::general());
+    }
 }
 
 bool style_serializer::write_fonts(xlnt::xml_node &fonts_node) const
@@ -1043,39 +1076,39 @@ bool style_serializer::write_borders(xlnt::xml_node &borders_node) const
     return true;
 }
 
-bool style_serializer::write_style_common(const alignment &style_alignment, const border &style_border, const fill &style_fill, const font &style_font, const number_format &style_number_format, const protection &style_protection, xml_node xf_node) const
+bool style_serializer::write_style_common(const common_style &style, xml_node xf_node) const
 {
-    xf_node.add_attribute("numFmtId", std::to_string(style_number_format.get_id()));
+    xf_node.add_attribute("numFmtId", std::to_string(style.get_number_format().get_id()));
      
-    auto font_id = std::distance(fonts_.begin(), std::find(fonts_.begin(), fonts_.end(), style_font));
+    auto font_id = std::distance(fonts_.begin(), std::find(fonts_.begin(), fonts_.end(), style.get_font()));
     xf_node.add_attribute("fontId", std::to_string(font_id));
 
-    if (style_fill.apply())
+    if (style.fill_applied())
     {
-        auto fill_id = std::distance(fills_.begin(), std::find(fills_.begin(), fills_.end(), style_fill));
+        auto fill_id = std::distance(fills_.begin(), std::find(fills_.begin(), fills_.end(), style.get_fill()));
         xf_node.add_attribute("fillId", std::to_string(fill_id));
     }
 
-    if (style_border.apply())
+    if (style.border_applied())
     {
-        auto border_id = std::distance(borders_.begin(), std::find(borders_.begin(), borders_.end(), style_border));
+        auto border_id = std::distance(borders_.begin(), std::find(borders_.begin(), borders_.end(), style.get_border()));
         xf_node.add_attribute("borderId", std::to_string(border_id));
     }
 
-    xf_node.add_attribute("applyNumberFormat", style_number_format.apply() ? "1" : "0");
-    xf_node.add_attribute("applyFill", style_fill.apply() ? "1" : "0");
-    xf_node.add_attribute("applyFont", style_font.apply() ? "1" : "0");
-    xf_node.add_attribute("applyBorder", style_border.apply() ? "1" : "0");
-    xf_node.add_attribute("applyAlignment", style_alignment.apply() ? "1" : "0");
-    xf_node.add_attribute("applyProtection", style_protection.apply() ? "1" : "0");
+    xf_node.add_attribute("applyNumberFormat", style.number_format_applied() ? "1" : "0");
+    xf_node.add_attribute("applyFill", style.fill_applied() ? "1" : "0");
+    xf_node.add_attribute("applyFont", style.font_applied() ? "1" : "0");
+    xf_node.add_attribute("applyBorder", style.border_applied() ? "1" : "0");
+    xf_node.add_attribute("applyAlignment", style.alignment_applied() ? "1" : "0");
+    xf_node.add_attribute("applyProtection", style.protection_applied() ? "1" : "0");
 
-    if (style_alignment.apply())
+    if (style.alignment_applied())
     {
         auto alignment_node = xf_node.add_child("alignment");
 
-        if (style_alignment.has_vertical())
+        if (style.get_alignment().has_vertical())
         {
-            switch (style_alignment.get_vertical())
+            switch (style.get_alignment().get_vertical())
             {
             case vertical_alignment::bottom:
                 alignment_node.add_attribute("vertical", "bottom");
@@ -1094,9 +1127,9 @@ bool style_serializer::write_style_common(const alignment &style_alignment, cons
             }
         }
 
-        if (style_alignment.has_horizontal())
+        if (style.get_alignment().has_horizontal())
         {
-            switch (style_alignment.get_horizontal())
+            switch (style.get_alignment().get_horizontal())
             {
             case horizontal_alignment::center:
                 alignment_node.add_attribute("horizontal", "center");
@@ -1121,12 +1154,12 @@ bool style_serializer::write_style_common(const alignment &style_alignment, cons
             }
         }
 
-        if (style_alignment.get_wrap_text())
+        if (style.get_alignment().get_wrap_text())
         {
             alignment_node.add_attribute("wrapText", "1");
         }
         
-        if (style_alignment.get_shrink_to_fit())
+        if (style.get_alignment().get_shrink_to_fit())
         {
             alignment_node.add_attribute("shrinkToFit", "1");
         }
@@ -1137,12 +1170,12 @@ bool style_serializer::write_style_common(const alignment &style_alignment, cons
 
 bool style_serializer::write_cell_style(const cell_style &style, xml_node &xf_node) const
 {
-    return write_style_common(style.get_alignment(), style.get_border(), style.get_fill(), style.get_font(), style.get_number_format(), style.get_protection(), xf_node);
+    return write_style_common(style, xf_node);
 }
 
 bool style_serializer::write_named_style(const named_style &style, xml_node &xf_node) const
 {
-    return write_style_common(style.get_alignment(), style.get_border(), style.get_fill(), style.get_font(), style.get_number_format(), style.get_protection(), xf_node);
+    return write_style_common(style, xf_node);
 }
 
 bool style_serializer::write_named_styles(xml_node &cell_styles_node, xml_node &styles_node) const
@@ -1249,11 +1282,12 @@ xml_document style_serializer::write_stylesheet()
     write_borders(borders_node);
     
     auto cell_style_xfs_node = root_node.add_child("cellStyleXfs");
-    auto cell_styles_node = root_node.add_child("cellStyles");
-    write_named_styles(root_node, cell_style_xfs_node);
 
     auto cell_xfs_node = root_node.add_child("cellXfs");
-    write_cell_styles(cell_styles_node);
+    write_cell_styles(cell_xfs_node);
+    
+    auto cell_styles_node = root_node.add_child("cellStyles");
+    write_named_styles(cell_style_xfs_node, cell_styles_node);
     
     auto dxfs_node = root_node.add_child("dxfs");
     write_dxfs(dxfs_node);
diff --git a/source/serialization/worksheet_serializer.cpp b/source/serialization/worksheet_serializer.cpp
index 227f6a86..77d117cc 100644
--- a/source/serialization/worksheet_serializer.cpp
+++ b/source/serialization/worksheet_serializer.cpp
@@ -197,7 +197,7 @@ bool worksheet_serializer::read_worksheet(const xml_document &xml)
 
                 if (has_style)
                 {
-                    cell.set_style(sheet_.get_parent().get_style(style_id));
+                    cell.set_style(sheet_.get_workbook().get_style(style_id));
                 }
             }
         }
diff --git a/source/styles/alignment.cpp b/source/styles/alignment.cpp
index 0c8c4c19..2f7e7c4c 100644
--- a/source/styles/alignment.cpp
+++ b/source/styles/alignment.cpp
@@ -90,14 +90,4 @@ std::string alignment::to_hash_string() const
     return hash_string;
 }
 
-bool alignment::apply() const
-{
-    return apply_;
-}
-
-void alignment::apply(bool value)
-{
-    apply_ = value;
-}
-
 } // namespace xlnt
diff --git a/source/styles/border.cpp b/source/styles/border.cpp
index 3cca63bd..e13565b0 100644
--- a/source/styles/border.cpp
+++ b/source/styles/border.cpp
@@ -149,14 +149,4 @@ std::string border::to_hash_string() const
     return hash_string;
 }
 
-bool border::apply() const
-{
-    return apply_;
-}
-
-void border::apply(bool value)
-{
-    apply_ = value;
-}
-
 } // namespace xlnt
diff --git a/source/styles/cell_style.cpp b/source/styles/cell_style.cpp
index a42646e0..dbf256dc 100644
--- a/source/styles/cell_style.cpp
+++ b/source/styles/cell_style.cpp
@@ -41,15 +41,10 @@ cell_style::cell_style(const cell_style &other)
 
 cell_style &cell_style::operator=(const cell_style &other)
 {
+    common_style::operator=(other);
+    
     parent_ = other.parent_;
     named_style_name_ = other.named_style_name_;
-    
-    alignment_ = other.alignment_;
-    border_ = other.border_;
-    fill_ = other.fill_;
-    font_ = other.font_;
-    number_format_ = other.number_format_;
-    protection_ = other.protection_;
 
     return *this;
 }
diff --git a/source/styles/common_style.cpp b/source/styles/common_style.cpp
index c738b145..8b9d36d3 100644
--- a/source/styles/common_style.cpp
+++ b/source/styles/common_style.cpp
@@ -26,6 +26,12 @@
 namespace xlnt {
 
 common_style::common_style()
+    : apply_alignment_(false),
+      apply_border_(false),
+      apply_fill_(false),
+      apply_font_(false),
+      apply_number_format_(false),
+      apply_protection_(false)
 {
 }
 
@@ -35,7 +41,13 @@ common_style::common_style(const common_style &other)
       fill_(other.fill_),
       font_(other.font_),
       number_format_(other.number_format_),
-      protection_(other.protection_)
+      protection_(other.protection_),
+      apply_alignment_(other.apply_alignment_),
+      apply_border_(other.apply_border_),
+      apply_fill_(other.apply_fill_),
+      apply_font_(other.apply_font_),
+      apply_number_format_(other.apply_number_format_),
+      apply_protection_(other.apply_protection_)
 {
 }
 
@@ -47,6 +59,13 @@ common_style &common_style::operator=(const xlnt::common_style &other)
     font_ = other.font_;
     number_format_ = other.number_format_;
     protection_ = other.protection_;
+    
+    apply_alignment_ = other.apply_alignment_;
+    apply_border_ = other.apply_border_;
+    apply_fill_ = other.apply_fill_;
+    apply_font_ = other.apply_font_;
+    apply_number_format_ = other.apply_number_format_;
+    apply_protection_ = other.apply_protection_;
 
     return *this;
 }
@@ -64,7 +83,7 @@ const alignment &common_style::get_alignment() const
 void common_style::set_alignment(const xlnt::alignment &new_alignment)
 {
     alignment_ = new_alignment;
-    alignment_.apply(true);
+    alignment_applied(true);
 }
 
 number_format &common_style::get_number_format()
@@ -80,7 +99,7 @@ const number_format &common_style::get_number_format() const
 void common_style::set_number_format(const xlnt::number_format &new_number_format)
 {
     number_format_ = new_number_format;
-    number_format_.apply(true);
+    number_format_applied(true);
 }
 
 border &common_style::get_border()
@@ -96,7 +115,7 @@ const border &common_style::get_border() const
 void common_style::set_border(const xlnt::border &new_border)
 {
     border_ = new_border;
-    border_.apply(true);
+    border_applied(true);
 }
 
 fill &common_style::get_fill()
@@ -112,7 +131,7 @@ const fill &common_style::get_fill() const
 void common_style::set_fill(const xlnt::fill &new_fill)
 {
     fill_ = new_fill;
-    fill_.apply(true);
+    fill_applied(true);
 }
 
 font &common_style::get_font()
@@ -128,7 +147,7 @@ const font &common_style::get_font() const
 void common_style::set_font(const xlnt::font &new_font)
 {
     font_ = new_font;
-    font_.apply(true);
+    font_applied(true);
 }
 
 protection &common_style::get_protection()
@@ -144,32 +163,92 @@ const protection &common_style::get_protection() const
 void common_style::set_protection(const xlnt::protection &new_protection)
 {
     protection_ = new_protection;
-    protection_.apply(true);
+    protection_applied(true);
 }
 
 std::string common_style::to_hash_string() const
 {
     std::string hash_string("common_style:");
     
-    hash_string.append(std::to_string(alignment_.apply()));
-    hash_string.append(alignment_.apply() ? std::to_string(alignment_.hash()) : ":");
+    hash_string.append(std::to_string(alignment_applied()));
+    hash_string.append(alignment_applied() ? std::to_string(alignment_.hash()) : ":");
 
-    hash_string.append(std::to_string(border_.apply()));
-    hash_string.append(border_.apply() ? std::to_string(border_.hash()) : ":");
+    hash_string.append(std::to_string(border_applied()));
+    hash_string.append(border_applied() ? std::to_string(border_.hash()) : ":");
 
-    hash_string.append(std::to_string(font_.apply()));
-    hash_string.append(font_.apply() ? std::to_string(font_.hash()) : ":");
+    hash_string.append(std::to_string(font_applied()));
+    hash_string.append(font_applied() ? std::to_string(font_.hash()) : ":");
 
-    hash_string.append(std::to_string(fill_.apply()));
-    hash_string.append(fill_.apply() ? std::to_string(fill_.hash()) : ":");
+    hash_string.append(std::to_string(fill_applied()));
+    hash_string.append(fill_applied() ? std::to_string(fill_.hash()) : ":");
 
-    hash_string.append(std::to_string(number_format_.apply()));
-    hash_string.append(number_format_.apply() ? std::to_string(number_format_.hash()) : ":");
+    hash_string.append(std::to_string(number_format_applied()));
+    hash_string.append(std::to_string(number_format_.hash()));
 
-    hash_string.append(std::to_string(protection_.apply()));
-    hash_string.append(protection_.apply() ? std::to_string(protection_.hash()) : ":");
+    hash_string.append(std::to_string(protection_applied()));
+    hash_string.append(protection_applied() ? std::to_string(protection_.hash()) : ":");
     
     return hash_string;
 }
 
+void common_style::alignment_applied(bool applied)
+{
+    apply_alignment_ = applied;
+}
+
+void common_style::border_applied(bool applied)
+{
+    apply_border_ = applied;
+}
+
+void common_style::fill_applied(bool applied)
+{
+    apply_fill_ = applied;
+}
+
+void common_style::font_applied(bool applied)
+{
+    apply_font_ = applied;
+}
+
+void common_style::number_format_applied(bool applied)
+{
+    apply_number_format_ = applied;
+}
+
+void common_style::protection_applied(bool applied)
+{
+    apply_protection_ = applied;
+}
+
+bool common_style::alignment_applied() const
+{
+    return apply_alignment_;
+}
+
+bool common_style::border_applied() const
+{
+    return apply_border_;
+}
+
+bool common_style::fill_applied() const
+{
+    return apply_fill_;
+}
+
+bool common_style::font_applied() const
+{
+    return apply_font_;
+}
+
+bool common_style::number_format_applied() const
+{
+    return apply_number_format_;
+}
+
+bool common_style::protection_applied() const
+{
+    return apply_protection_;
+}
+
 } // namespace xlnt
diff --git a/source/styles/fill.cpp b/source/styles/fill.cpp
index 454beb4a..e4a1b1ae 100644
--- a/source/styles/fill.cpp
+++ b/source/styles/fill.cpp
@@ -267,14 +267,4 @@ double fill::get_gradient_bottom() const
     return gradient_path_bottom_;
 }
 
-bool fill::apply() const
-{
-    return apply_;
-}
-
-void fill::apply(bool value)
-{
-    apply_ = value;
-}
-
 } // namespace xlnt
diff --git a/source/styles/font.cpp b/source/styles/font.cpp
index a6e0a0b3..db93bb08 100644
--- a/source/styles/font.cpp
+++ b/source/styles/font.cpp
@@ -146,14 +146,4 @@ std::string font::to_hash_string() const
     return hash_string;
 }
 
-bool font::apply() const
-{
-    return apply_;
-}
-
-void font::apply(bool value)
-{
-    apply_ = value;
-}
-
 } // namespace xlnt
diff --git a/source/styles/number_format.cpp b/source/styles/number_format.cpp
index 1f1be61f..c843b6c5 100644
--- a/source/styles/number_format.cpp
+++ b/source/styles/number_format.cpp
@@ -1094,9 +1094,9 @@ std::string number_format::get_format_string() const
 std::string number_format::to_hash_string() const
 {
     std::string hash_string("number_format");
-    
-//    hash_string.append(std::to_string(id_));
     hash_string.append(format_string_);
+    hash_string.append("|||");
+    hash_string.append(std::to_string(id_));
 
     return hash_string;
 }
@@ -1175,14 +1175,4 @@ std::string number_format::format(long double number, calendar base_date) const
     return format_number(number, format_string_, base_date);
 }
 
-bool number_format::apply() const
-{
-    return apply_;
-}
-
-void number_format::apply(bool value)
-{
-    apply_ = value;
-}
-
 } // namespace xlnt
diff --git a/source/styles/protection.cpp b/source/styles/protection.cpp
index f173a15a..d728e087 100644
--- a/source/styles/protection.cpp
+++ b/source/styles/protection.cpp
@@ -54,14 +54,4 @@ std::string protection::to_hash_string() const
     return hash_string;
 }
 
-bool protection::apply() const
-{
-    return apply_;
-}
-
-void protection::apply(bool value)
-{
-    apply_ = value;
-}
-
 } // namespace xlnt
diff --git a/source/workbook/workbook.cpp b/source/workbook/workbook.cpp
index 87b28be4..8e1f6fb4 100644
--- a/source/workbook/workbook.cpp
+++ b/source/workbook/workbook.cpp
@@ -607,19 +607,47 @@ std::vector<named_range> workbook::get_named_ranges() const
 
 std::size_t workbook::add_style(const cell_style &style)
 {
+    cell_style style_copy = style;
+    
+    //TODO this is ugly
+    if (!style.get_number_format().has_id())
+    {
+        bool match = false;
+        
+        for (std::size_t i = 0; i < d_->cell_styles_.size(); i++)
+        {
+            if (d_->cell_styles_.at(i).get_number_format().get_format_string() == style_copy.get_number_format().get_format_string())
+            {
+                style_copy.set_number_format(d_->cell_styles_.at(i).get_number_format());
+                match = true;
+                break;
+            }
+        }
+        
+        if (!match)
+        {
+            style_copy.get_number_format().set_id(d_->next_custom_format_id_++);
+        }
+    }
+    
     for (std::size_t i = 0; i < d_->cell_styles_.size(); i++)
     {
-        if (d_->cell_styles_[i] == style)
+        if (d_->cell_styles_[i] == style_copy)
         {
             return i;
         }
     }
     
-    d_->cell_styles_.push_back(style);
+    d_->cell_styles_.push_back(style_copy);
     
     return d_->cell_styles_.size() - 1;
 }
 
+void workbook::clear_styles()
+{
+    d_->cell_styles_.clear();
+}
+
 cell_style &workbook::get_style(std::size_t style_index)
 {
     return d_->cell_styles_.at(style_index);