diff --git a/include/xlnt/packaging/relationship.hpp b/include/xlnt/packaging/relationship.hpp
index 00d7e942..2dcbb4af 100644
--- a/include/xlnt/packaging/relationship.hpp
+++ b/include/xlnt/packaging/relationship.hpp
@@ -115,7 +115,7 @@ public:
     /// <summary>
     /// Returns a string of the form rId# that identifies the relationship.
     /// </summary>
-    std::string id() const;
+    const std::string& id() const;
 
     /// <summary>
     /// Returns the type of this relationship.
@@ -130,12 +130,12 @@ public:
     /// <summary>
     /// Returns the URI of the package part this relationship points to.
     /// </summary>
-    uri source() const;
+    const uri &source() const;
 
     /// <summary>
     /// Returns the URI of the package part this relationship points to.
     /// </summary>
-    uri target() const;
+    const uri &target() const;
 
     /// <summary>
     /// Returns true if and only if rhs is equal to this relationship.
diff --git a/include/xlnt/packaging/uri.hpp b/include/xlnt/packaging/uri.hpp
index 7e945168..66d6358e 100644
--- a/include/xlnt/packaging/uri.hpp
+++ b/include/xlnt/packaging/uri.hpp
@@ -123,7 +123,7 @@ public:
     /// Returns the path of this URI.
     /// E.g. the path of http://example.com/document is "/document"
     /// </summary>
-    class path path() const;
+    const class path& path() const;
 
     /// <summary>
     /// Returns true if this URI has a non-null query string section.
diff --git a/source/packaging/relationship.cpp b/source/packaging/relationship.cpp
index 7788be5a..9c104e08 100644
--- a/source/packaging/relationship.cpp
+++ b/source/packaging/relationship.cpp
@@ -36,7 +36,7 @@ relationship::relationship(
 {
 }
 
-std::string relationship::id() const
+const std::string& relationship::id() const
 {
     return id_;
 }
@@ -46,12 +46,12 @@ target_mode relationship::target_mode() const
     return mode_;
 }
 
-uri relationship::source() const
+const uri &relationship::source() const
 {
     return source_;
 }
 
-uri relationship::target() const
+const uri &relationship::target() const
 {
     return target_;
 }
diff --git a/source/packaging/uri.cpp b/source/packaging/uri.cpp
index 10b43777..850234a3 100644
--- a/source/packaging/uri.cpp
+++ b/source/packaging/uri.cpp
@@ -16,7 +16,7 @@ std::string uri::to_string() const
     return path_.string();
 }
 
-path uri::path() const
+const path& uri::path() const
 {
     return path_;
 }
diff --git a/source/workbook/workbook.cpp b/source/workbook/workbook.cpp
index 55c460c4..c4739f03 100644
--- a/source/workbook/workbook.cpp
+++ b/source/workbook/workbook.cpp
@@ -28,16 +28,6 @@
 #include <functional>
 #include <set>
 
-#include <detail/constants.hpp>
-#include <detail/default_case.hpp>
-#include <detail/implementations/cell_impl.hpp>
-#include <detail/implementations/workbook_impl.hpp>
-#include <detail/implementations/worksheet_impl.hpp>
-#include <detail/serialization/excel_thumbnail.hpp>
-#include <detail/serialization/vector_streambuf.hpp>
-#include <detail/serialization/open_stream.hpp>
-#include <detail/serialization/xlsx_consumer.hpp>
-#include <detail/serialization/xlsx_producer.hpp>
 #include <xlnt/cell/cell.hpp>
 #include <xlnt/packaging/manifest.hpp>
 #include <xlnt/packaging/relationship.hpp>
@@ -61,12 +51,22 @@
 #include <xlnt/worksheet/header_footer.hpp>
 #include <xlnt/worksheet/range.hpp>
 #include <xlnt/worksheet/worksheet.hpp>
+#include <detail/constants.hpp>
+#include <detail/default_case.hpp>
+#include <detail/implementations/cell_impl.hpp>
+#include <detail/implementations/workbook_impl.hpp>
+#include <detail/implementations/worksheet_impl.hpp>
+#include <detail/serialization/excel_thumbnail.hpp>
+#include <detail/serialization/open_stream.hpp>
+#include <detail/serialization/vector_streambuf.hpp>
+#include <detail/serialization/xlsx_consumer.hpp>
+#include <detail/serialization/xlsx_producer.hpp>
 
 namespace {
 
 using xlnt::detail::open_stream;
 
-template<typename T>
+template <typename T>
 std::vector<T> keys(const std::vector<std::pair<T, xlnt::variant>> &container)
 {
     auto result = std::vector<T>();
@@ -80,7 +80,7 @@ std::vector<T> keys(const std::vector<std::pair<T, xlnt::variant>> &container)
     return result;
 }
 
-template<typename T>
+template <typename T>
 bool contains(const std::vector<std::pair<T, xlnt::variant>> &container, const T key)
 {
     for (const auto &iter : container)
@@ -451,29 +451,29 @@ workbook workbook::empty()
     stylesheet.parent = &wb;
 
     auto default_border = border()
-        .side(border_side::bottom, border::border_property())
-        .side(border_side::top, border::border_property())
-        .side(border_side::start, border::border_property())
-        .side(border_side::end, border::border_property())
-        .side(border_side::diagonal, border::border_property());
+                              .side(border_side::bottom, border::border_property())
+                              .side(border_side::top, border::border_property())
+                              .side(border_side::start, border::border_property())
+                              .side(border_side::end, border::border_property())
+                              .side(border_side::diagonal, border::border_property());
     wb.d_->stylesheet_.get().borders.push_back(default_border);
 
     auto default_fill = fill(pattern_fill()
-        .type(pattern_fill_type::none));
+                                 .type(pattern_fill_type::none));
     stylesheet.fills.push_back(default_fill);
     auto gray125_fill = pattern_fill()
-        .type(pattern_fill_type::gray125);
+                            .type(pattern_fill_type::gray125);
     stylesheet.fills.push_back(gray125_fill);
 
     auto default_font = font()
-        .name("Calibri")
-        .size(12)
-        .scheme("minor")
-        .family(2)
-        .color(theme_color(1));
+                            .name("Calibri")
+                            .size(12)
+                            .scheme("minor")
+                            .family(2)
+                            .color(theme_color(1));
     stylesheet.fonts.push_back(default_font);
 
-	wb.create_builtin_style(0)
+    wb.create_builtin_style(0)
         .border(default_border)
         .fill(default_fill)
         .font(default_font)
@@ -550,7 +550,7 @@ void workbook::register_package_part(relationship_type type)
 void workbook::register_workbook_part(relationship_type type)
 {
     auto wb_rel = manifest().relationship(path("/"), relationship_type::office_document);
-    auto wb_path = manifest().canonicalize({ wb_rel });
+    auto wb_path = manifest().canonicalize({wb_rel});
 
     if (!manifest().has_relationship(wb_path, type))
     {
@@ -738,22 +738,35 @@ worksheet workbook::create_sheet()
     std::string title = "Sheet1";
     int index = 1;
 
+    // make a unique sheet name. Sheet<1...n>
     while (contains(title))
     {
         title = "Sheet" + std::to_string(++index);
     }
-
+    // unique sheet id
     size_t sheet_id = 1;
     for (const auto ws : *this)
     {
         sheet_id = std::max(sheet_id, ws.id() + 1);
     }
-    std::string sheet_filename = "sheet" + std::to_string(sheet_id) + ".xml";
-
     d_->worksheets_.push_back(detail::worksheet_impl(this, sheet_id, title));
-
+    // unique sheet file name
     auto workbook_rel = d_->manifest_.relationship(path("/"), relationship_type::office_document);
-    uri relative_sheet_uri(path("worksheets").append(sheet_filename).string());
+    auto workbook_files = d_->manifest_.relationships(workbook_rel.target().path());
+    auto rel_vec_contains = [&workbook_files](const xlnt::path &new_file_id) {
+        return workbook_files.end() != std::find_if(workbook_files.begin(), workbook_files.end(), [&new_file_id](const xlnt::relationship &rel) {
+            return rel.target().path() == new_file_id;
+        });
+    };
+
+    size_t file_id = sheet_id;
+    xlnt::path sheet_relative_path;
+    do
+    {
+        sheet_relative_path = path("worksheets").append("sheet" + std::to_string(file_id++) + ".xml");
+    } while (rel_vec_contains(sheet_relative_path));
+
+    uri relative_sheet_uri(sheet_relative_path.string());
     auto absolute_sheet_path = path("/xl").append(relative_sheet_uri.path());
     d_->manifest_.register_override_type(
         absolute_sheet_path, "application/vnd.openxmlformats-officedocument.spreadsheetml.worksheet+xml");
@@ -1025,7 +1038,8 @@ void workbook::remove_sheet(worksheet ws)
     for (auto &title_rel_id_pair : d_->sheet_title_rel_id_map_)
     {
         title_rel_id_pair.second = rel_id_map.count(title_rel_id_pair.second) > 0
-            ? rel_id_map[title_rel_id_pair.second] : title_rel_id_pair.second;
+            ? rel_id_map[title_rel_id_pair.second]
+            : title_rel_id_pair.second;
     }
 
     update_sheet_properties();
@@ -1390,7 +1404,7 @@ style workbook::create_style(const std::string &name)
 
 style workbook::create_builtin_style(const std::size_t builtin_id)
 {
-	return d_->stylesheet_.get().create_builtin_style(builtin_id);
+    return d_->stylesheet_.get().create_builtin_style(builtin_id);
 }
 
 style workbook::style(const std::string &name)
@@ -1563,69 +1577,83 @@ void workbook::update_sheet_properties()
     }
 }
 
-void workbook::reorder_relationships()
+namespace {
+// true if a sheet index is != worksheet relationship index
+bool needs_reorder(const std::unordered_map<std::string, std::string> &title_to_rels,
+    const std::vector<std::string> &titles,
+    std::vector<std::string> &relation_ids)
 {
-    const auto wb_rel = manifest().relationship(path("/"), relationship_type::office_document);
-    const auto wb_path = wb_rel.target().path();
-    const auto relationships = manifest().relationships(wb_path);
-    std::unordered_map<std::string, relationship> rel_map;
-    const auto titles = sheet_titles();
-    const auto title_rel_id_map = d_->sheet_title_rel_id_map_;
-    bool needs_reorder = false;
-
-    for (const auto &rel : relationships)
+    bool all_match = true;
+    for (std::size_t title_index = 0; title_index < titles.size(); ++title_index)
     {
-        rel_map[rel.id()] = rel;
-
-        if (rel.type() == relationship_type::worksheet)
+        const auto &rel = title_to_rels.at(titles[title_index]);
+        relation_ids.push_back(rel);
+        const auto expected_rel_id = "rId" + std::to_string(title_index + 1);
+        if (rel != expected_rel_id)
         {
-            for (auto title_index = std::size_t(0); title_index < titles.size(); ++title_index)
-            {
-                const auto title = titles[title_index];
-
-                if (title_rel_id_map.at(title) == rel.id())
-                {
-                    const auto expected_rel_id = "rId" + std::to_string(title_index + 1);
-
-                    if (expected_rel_id != rel.id())
-                    {
-                        needs_reorder = true;
-                    }
-
-                    break;
-                }
-            }
+            all_match = false;
         }
     }
+    return !all_match; // if all are as expected, reorder not required
+};
 
-    if (!needs_reorder)
+struct rel_id_sorter
+{
+    // true if lhs < rhs
+    bool operator()(const xlnt::relationship &lhs, const xlnt::relationship &rhs)
+    {
+        // format is rTd<decimal number 1..n>
+        if (lhs.id().size() < rhs.id().size()) // a number with more digits will be larger
+        {
+            return true;
+        }
+        return lhs.id() < rhs.id();
+    }
+};
+} // namespace
+
+void workbook::reorder_relationships()
+{
+    const auto titles = sheet_titles();
+    // the relation ID corresponding to the title at the same index is copied into here
+    std::vector<std::string> worksheet_rel_ids;
+    worksheet_rel_ids.reserve(titles.size());
+    if (!needs_reorder(d_->sheet_title_rel_id_map_, titles, worksheet_rel_ids))
     {
         return;
     }
-
-    for (const auto &rel : relationships)
+    // copy of existing relations
+    const auto wb_rel_target = manifest().relationship(path("/"), relationship_type::office_document).target();
+    auto rel_copy = manifest().relationships(wb_rel_target.path());
+    std::sort(rel_copy.begin(), rel_copy.end(), rel_id_sorter{});
+    // clear existing relations
+    for (const auto &rel : rel_copy)
     {
-        manifest().unregister_relationship(uri(wb_path.string()), rel.id());
+        manifest().unregister_relationship(wb_rel_target, rel.id());
     }
-
-    for (auto index = std::size_t(0); index < rel_map.size(); ++index)
+    // create new relations
+    std::size_t index = 0;
+    auto new_id = [&index]() { return "rId" + std::to_string(++index); }; // ids start from 1
+    // worksheets first
+    while (index < worksheet_rel_ids.size())
     {
-        auto rel_id = "rId" + std::to_string(index + 1);
-        auto old_rel_id = std::string();
+        auto rel_it = std::find_if(rel_copy.begin(), rel_copy.end(),
+            [&](const relationship &rel) { return rel.id() == worksheet_rel_ids[index]; });
 
-        if (index < titles.size())
+        std::string rel_id = new_id();
+        d_->sheet_title_rel_id_map_.at(titles[index - 1]) = rel_id; // update title -> relation mapping
+        manifest().register_relationship(relationship(rel_id, rel_it->type(),
+            rel_it->source(), rel_it->target(), rel_it->target_mode()));
+    }
+    // then all the other relations in the same order they started (just new indices)
+    for (const auto &old_rel : rel_copy)
+    {
+        if (old_rel.type() == relationship_type::worksheet)
         {
-            auto title = titles[index];
-            old_rel_id = title_rel_id_map.at(title);
-            d_->sheet_title_rel_id_map_[title] = rel_id;
-        } else {
-            old_rel_id = "rId" + std::to_string(index - titles.size() + 2);
+            continue;
         }
-
-        auto old_rel = rel_map[old_rel_id];
-        auto new_rel = relationship(rel_id, old_rel.type(),
-            old_rel.source(), old_rel.target(), old_rel.target_mode());
-        manifest().register_relationship(new_rel);
+        manifest().register_relationship(relationship(new_id(), old_rel.type(),
+            old_rel.source(), old_rel.target(), old_rel.target_mode()));
     }
 }
 
diff --git a/tests/data/Issue279_workbook_delete_rename.xlsx b/tests/data/Issue279_workbook_delete_rename.xlsx
new file mode 100644
index 00000000..981af413
Binary files /dev/null and b/tests/data/Issue279_workbook_delete_rename.xlsx differ
diff --git a/tests/helpers/xml_helper.hpp b/tests/helpers/xml_helper.hpp
index 9c051536..9a90e9e3 100644
--- a/tests/helpers/xml_helper.hpp
+++ b/tests/helpers/xml_helper.hpp
@@ -3,17 +3,17 @@
 #include <sstream>
 #include <unordered_set>
 
+#include <xlnt/packaging/manifest.hpp>
+#include <xlnt/workbook/workbook.hpp>
 #include <detail/external/include_libstudxml.hpp>
 #include <detail/serialization/vector_streambuf.hpp>
 #include <detail/serialization/zstream.hpp>
-#include <xlnt/packaging/manifest.hpp>
-#include <xlnt/workbook/workbook.hpp>
 
 class xml_helper
 {
 public:
     static bool compare_files(const std::string &left,
-		const std::string &right, const std::string &content_type)
+        const std::string &right, const std::string &content_type)
     {
         // content types are stored in unordered maps, too complicated to compare
         if (content_type == "[Content_Types].xml")
@@ -34,7 +34,7 @@ public:
         }
 
         auto is_xml = (content_type.substr(0, 12) == "application/"
-            && content_type.substr(content_type.size() - 4) == "+xml")
+                          && content_type.substr(content_type.size() - 4) == "+xml")
             || content_type == "application/xml"
             || content_type == "[Content_Types].xml"
             || content_type == "application/vnd.openxmlformats-officedocument.vmlDrawing";
@@ -63,8 +63,7 @@ public:
         bool difference = false;
         auto right_iter = right_parser.begin();
 
-        auto is_whitespace = [](const std::string &v)
-        {
+        auto is_whitespace = [](const std::string &v) {
             return v.find_first_not_of("\n\r\t ") == std::string::npos;
         };
 
@@ -198,26 +197,26 @@ public:
             ++right_iter;
         }
 
-		if (difference && !suppress_debug_info)
-		{
-			std::cout << "documents don't match" << std::endl;
+        if (difference && !suppress_debug_info)
+        {
+            std::cout << "documents don't match" << std::endl;
 
-			std::cout << "left:" << std::endl;
+            std::cout << "left:" << std::endl;
             for (auto c : left)
             {
                 std::cout << c << std::flush;
             }
-			std::cout << std::endl;
+            std::cout << std::endl;
 
-			std::cout << "right:" << std::endl;
+            std::cout << "right:" << std::endl;
             for (auto c : right)
             {
                 std::cout << c << std::flush;
             }
-			std::cout << std::endl;
-		}
+            std::cout << std::endl;
+        }
 
-		return !difference;
+        return !difference;
     }
 
     static bool compare_relationships(const xlnt::manifest &left,
@@ -271,27 +270,26 @@ public:
         return true;
     }
 
-	static bool xlsx_archives_match(const std::vector<std::uint8_t> &left,
+    static bool xlsx_archives_match(const std::vector<std::uint8_t> &left,
         const std::vector<std::uint8_t> &right)
-	{
+    {
         xlnt::detail::vector_istreambuf left_buffer(left);
         std::istream left_stream(&left_buffer);
         xlnt::detail::izstream left_archive(left_stream);
 
-		const auto left_info = left_archive.files();
+        const auto left_info = left_archive.files();
 
         xlnt::detail::vector_istreambuf right_buffer(right);
         std::istream right_stream(&right_buffer);
         xlnt::detail::izstream right_archive(right_stream);
 
-		const auto right_info = right_archive.files();
+        const auto right_info = right_archive.files();
 
         auto difference_is_missing_calc_chain = false;
 
         if (std::abs(int(left_info.size()) - int(right_info.size())) == 1)
         {
-            auto is_calc_chain = [](const xlnt::path &p)
-            {
+            auto is_calc_chain = [](const xlnt::path &p) {
                 return p.filename() == "calcChain.xml";
             };
 
@@ -306,7 +304,7 @@ public:
             }
         }
 
-		if (left_info.size() != right_info.size() && ! difference_is_missing_calc_chain)
+        if (left_info.size() != right_info.size() && !difference_is_missing_calc_chain)
         {
             std::cout << "left has a different number of files than right" << std::endl;
 
@@ -338,12 +336,41 @@ public:
 
         if (!compare_relationships(left_manifest, right_manifest))
         {
+            std::cout << "relationship mismatch\n"
+                      << "Left:\n";
+            for (const auto &part : left_manifest.parts())
+            {
+                std::cout << "-part: " << part.string() << '\n';
+                auto rels = left_manifest.relationships(part);
+                for (auto &rel : rels)
+                {
+                    std::cout << rel.id() << ':' 
+                        << static_cast<int>(rel.type()) 
+                        << ':' << static_cast<int>(rel.target_mode()) 
+                        << ':' << rel.source().path().string() 
+                        << ':' << rel.target().path().string() << '\n';
+                }
+            }
+            std::cout << "\nRight:\n";
+            for (const auto &part : right_manifest.parts())
+            {
+                std::cout << "-part: " << part.string() << '\n';
+                auto rels = right_manifest.relationships(part);
+                for (auto &rel : rels)
+                {
+                    std::cout << rel.id() 
+                        << ':' << static_cast<int>(rel.type()) 
+                        << ':' << static_cast<int>(rel.target_mode()) 
+                        << ':' << rel.source().path().string() 
+                        << ':' << rel.target().path().string() << '\n';
+                }
+            }
             return false;
         }
 
-		for (auto left_member : left_info)
-		{
-			if (!right_archive.has_file(left_member))
+        for (auto left_member : left_info)
+        {
+            if (!right_archive.has_file(left_member))
             {
                 if (difference_is_missing_calc_chain)
                 {
@@ -357,32 +384,34 @@ public:
             }
 
             auto left_content_type = left_member.string() == "[Content_Types].xml"
-                ? "[Content_Types].xml" : left_manifest.content_type(left_member);
+                ? "[Content_Types].xml"
+                : left_manifest.content_type(left_member);
             auto right_content_type = left_member.string() == "[Content_Types].xml"
-                ? "[Content_Types].xml" : right_manifest.content_type(left_member);
+                ? "[Content_Types].xml"
+                : right_manifest.content_type(left_member);
 
             if (left_content_type != right_content_type)
             {
                 std::cout << "content types differ: "
-                    << left_member.string()
-                    << " "
-                    << left_content_type
-                    << " "
-                    << right_content_type
-                    << std::endl;
+                          << left_member.string()
+                          << " "
+                          << left_content_type
+                          << " "
+                          << right_content_type
+                          << std::endl;
                 match = false;
                 break;
             }
 
             if (!compare_files(left_archive.read(left_member),
-                right_archive.read(left_member), left_content_type))
-			{
-				std::cout << left_member.string() << std::endl;
+                    right_archive.read(left_member), left_content_type))
+            {
+                std::cout << left_member.string() << std::endl;
                 match = false;
                 break;
-			}
-		}
+            }
+        }
 
-		return match;
-	}
+        return match;
+    }
 };
diff --git a/tests/workbook/workbook_test_suite.cpp b/tests/workbook/workbook_test_suite.cpp
index 86e8ae1e..b1a83df8 100644
--- a/tests/workbook/workbook_test_suite.cpp
+++ b/tests/workbook/workbook_test_suite.cpp
@@ -66,6 +66,7 @@ public:
         register_test(test_comparison);
         register_test(test_id_gen);
         register_test(test_load_file);
+        register_test(test_Issue279);
     }
 
     void test_active_sheet()
@@ -460,11 +461,35 @@ public:
         // load with vector
         std::ifstream file_reader3(file.string(), std::ios::binary);
         file_reader3.unsetf(std::ios::skipws);
-        std::vector<uint8_t> data(std::istream_iterator<uint8_t>{file_reader3}, 
-                                  std::istream_iterator<uint8_t>());
+        std::vector<uint8_t> data(std::istream_iterator<uint8_t>{file_reader3},
+            std::istream_iterator<uint8_t>());
         xlnt::workbook wb_load5;
         wb_load5.load(data);
         xlnt_assert_equals(wb_path, wb_load5);
     }
+
+    void test_Issue279()
+    {
+        xlnt::workbook wb(path_helper::test_file("Issue279_workbook_delete_rename.xlsx"));
+        while (wb.sheet_count() > 1)
+        {
+            if (wb[1].title() != "BOM")
+            {
+                wb.remove_sheet(wb[1]);
+            }
+            else
+            {
+                wb.remove_sheet(wb[0]);
+            }
+        }
+        // get sheet bom change title
+        auto ws1 = wb.sheet_by_index(0);
+        ws1.title("checkedBom");
+        // report sheet
+        auto ws2 = wb.create_sheet(1);
+        ws2.title("REPORT");
+        //save a copy file
+        wb.save("temp.xlsx");
+    }
 };
 static workbook_test_suite x;
\ No newline at end of file