diff --git a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheets.cs b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheets.cs
index 90e3839..6b4da79 100644
--- a/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheets.cs
+++ b/ClosedXML/ClosedXML/ClosedXML/Excel/XLWorksheets.cs
@@ -12,7 +12,7 @@
         #region Constructor
 
         private readonly XLWorkbook m_workbook;
-        private readonly Dictionary<String, XLWorksheet> m_worksheets = new Dictionary<String, XLWorksheet>();
+        private readonly Dictionary<String, XLWorksheet> _worksheets = new Dictionary<String, XLWorksheet>();
 
         #endregion
 
@@ -31,7 +31,7 @@
 
         public IEnumerator<XLWorksheet> GetEnumerator()
         {
-            return ((IEnumerable<XLWorksheet>)m_worksheets.Values).GetEnumerator();
+            return ((IEnumerable<XLWorksheet>)_worksheets.Values).GetEnumerator();
         }
 
         #endregion
@@ -41,13 +41,13 @@
         public int Count
         {
             [DebuggerStepThrough]
-            get { return m_worksheets.Count; }
+            get { return _worksheets.Count; }
         }
 
         public bool TryGetWorksheet(string sheetName, out IXLWorksheet worksheet)
         {
             XLWorksheet w;
-            if (m_worksheets.TryGetValue(sheetName, out w))
+            if (_worksheets.TryGetValue(sheetName, out w))
             {
                 worksheet = w;
                 return true;
@@ -59,10 +59,10 @@
         public IXLWorksheet Worksheet(String sheetName)
         {
             XLWorksheet w;
-            if (m_worksheets.TryGetValue(sheetName, out w))
+            if (_worksheets.TryGetValue(sheetName, out w))
                 return w;
 
-            var wss = m_worksheets.Where(ws => ws.Key.ToLower().Equals(sheetName.ToLower()));
+            var wss = _worksheets.Where(ws => ws.Key.ToLower().Equals(sheetName.ToLower()));
 
             if (wss.Any())
                 return wss.First().Value;
@@ -72,7 +72,7 @@
 
         public IXLWorksheet Worksheet(Int32 position)
         {
-            int wsCount = m_worksheets.Values.Count(w => w.Position == position);
+            int wsCount = _worksheets.Values.Count(w => w.Position == position);
             if (wsCount == 0)
                 throw new Exception("There isn't a worksheet associated with that position.");
 
@@ -82,33 +82,34 @@
                     "Can't retrieve a worksheet because there are multiple worksheets associated with that position.");
             }
 
-            return m_worksheets.Values.Single(w => w.Position == position);
+            return _worksheets.Values.Single(w => w.Position == position);
         }
 
         public IXLWorksheet Add(String sheetName)
         {
             var sheet = new XLWorksheet(sheetName, m_workbook);
-            m_worksheets.Add(sheetName, sheet);
-            sheet._position = m_worksheets.Count;
+            _worksheets.Add(sheetName, sheet);
+            sheet._position = _worksheets.Count;
             return sheet;
         }
 
         public IXLWorksheet Add(String sheetName, Int32 position)
         {
+            _worksheets.Values.Where(w => w._position >= position).ForEach(w => w._position += 1);
             var sheet = new XLWorksheet(sheetName, m_workbook);
-            m_worksheets.Add(sheetName, sheet);
+            _worksheets.Add(sheetName, sheet);
             sheet._position = position;
             return sheet;
         }
 
         public void Delete(String sheetName)
         {
-            Delete(m_worksheets[sheetName].Position);
+            Delete(_worksheets[sheetName].Position);
         }
 
         public void Delete(Int32 position)
         {
-            int wsCount = m_worksheets.Values.Count(w => w.Position == position);
+            int wsCount = _worksheets.Values.Count(w => w.Position == position);
             if (wsCount == 0)
                 throw new Exception("There isn't a worksheet associated with that index.");
 
@@ -116,17 +117,17 @@
                 throw new Exception(
                     "Can't delete the worksheet because there are multiple worksheets associated with that index.");
 
-            var ws = m_worksheets.Values.Single(w => w.Position == position);
+            var ws = _worksheets.Values.Single(w => w.Position == position);
             if (!StringExtensions.IsNullOrWhiteSpace(ws.RelId) && !Deleted.Contains(ws.RelId))
                 Deleted.Add(ws.RelId);
 
-            m_worksheets.RemoveAll(w => w.Position == position);
-            m_worksheets.Values.Where(w => w.Position > position).ForEach(w => (w)._position -= 1);
+            _worksheets.RemoveAll(w => w.Position == position);
+            _worksheets.Values.Where(w => w.Position > position).ForEach(w => (w)._position -= 1);
         }
 
         IEnumerator<IXLWorksheet> IEnumerable<IXLWorksheet>.GetEnumerator()
         {
-            return m_worksheets.Values.Cast<IXLWorksheet>().GetEnumerator();
+            return _worksheets.Values.Cast<IXLWorksheet>().GetEnumerator();
         }
 
         IEnumerator IEnumerable.GetEnumerator()
@@ -152,11 +153,11 @@
 
         public void Rename(String oldSheetName, String newSheetName)
         {
-            if (StringExtensions.IsNullOrWhiteSpace(oldSheetName) || !m_worksheets.ContainsKey(oldSheetName)) return;
+            if (StringExtensions.IsNullOrWhiteSpace(oldSheetName) || !_worksheets.ContainsKey(oldSheetName)) return;
 
-            var ws = m_worksheets[oldSheetName];
-            m_worksheets.Remove(oldSheetName);
-            m_worksheets.Add(newSheetName, ws);
+            var ws = _worksheets[oldSheetName];
+            _worksheets.Remove(oldSheetName);
+            _worksheets.Add(newSheetName, ws);
         }
     }
 }
\ No newline at end of file
diff --git a/ClosedXML/ClosedXML/ClosedXML_Tests/ClosedXML_Tests.csproj b/ClosedXML/ClosedXML/ClosedXML_Tests/ClosedXML_Tests.csproj
index 324d39d..9f91586 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Tests/ClosedXML_Tests.csproj
+++ b/ClosedXML/ClosedXML/ClosedXML_Tests/ClosedXML_Tests.csproj
@@ -142,7 +142,6 @@
     <EmbeddedResource Include="Resource\Examples\Misc\LambdaExpressions.xlsx" />
     <EmbeddedResource Include="Resource\Examples\Misc\MergeCells.xlsx" />
     <EmbeddedResource Include="Resource\Examples\Misc\MergeMoves.xlsx" />
-    <EmbeddedResource Include="Resource\Examples\Misc\MultipleSheets.xlsx" />
     <EmbeddedResource Include="Resource\Examples\Misc\Outline.xlsx" />
     <EmbeddedResource Include="Resource\Examples\Misc\SheetProtection.xlsx" />
     <EmbeddedResource Include="Resource\Examples\Misc\ShiftingFormulas.xlsx" />
diff --git a/ClosedXML/ClosedXML/ClosedXML_Tests/Examples/MiscTests.cs b/ClosedXML/ClosedXML/ClosedXML_Tests/Examples/MiscTests.cs
index faa489f..cd6283a 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Tests/Examples/MiscTests.cs
+++ b/ClosedXML/ClosedXML/ClosedXML_Tests/Examples/MiscTests.cs
@@ -108,11 +108,6 @@
             TestHelper.RunTestExample<MergeMoves>(@"Misc\MergeMoves.xlsx");
         }
         [TestMethod]
-        public void MultipleSheets()
-        {
-            TestHelper.RunTestExample<MultipleSheets>(@"Misc\MultipleSheets.xlsx");
-        }
-        [TestMethod]
         public void Outline()
         {
             TestHelper.RunTestExample<Outline>(@"Misc\Outline.xlsx");
diff --git a/ClosedXML/ClosedXML/ClosedXML_Tests/Excel/Worksheets/XLWorksheetTests.cs b/ClosedXML/ClosedXML/ClosedXML_Tests/Excel/Worksheets/XLWorksheetTests.cs
index 2ad2ef2..d3ff18b 100644
--- a/ClosedXML/ClosedXML/ClosedXML_Tests/Excel/Worksheets/XLWorksheetTests.cs
+++ b/ClosedXML/ClosedXML/ClosedXML_Tests/Excel/Worksheets/XLWorksheetTests.cs
@@ -9,7 +9,7 @@
     [TestClass()]
     public class XLWorksheetTests
     {
-        [TestMethod()]
+        [TestMethod]
         public void MergedRanges()
         {
             var ws = new XLWorkbook().Worksheets.Add("Sheet1");
@@ -21,6 +21,61 @@
             Assert.AreEqual("A1:B2", ws.MergedRanges.First().RangeAddress.ToStringRelative());
             Assert.AreEqual("D2:E2", ws.MergedRanges.Last().RangeAddress.ToStringRelative());
         }
+        
+        [TestMethod]
+        public void InsertingSheets1()
+        {
+            var wb = new XLWorkbook();
+            wb.Worksheets.Add("Sheet1");
+            wb.Worksheets.Add("Sheet2");
+            wb.Worksheets.Add("Sheet3");
 
+            Assert.AreEqual("Sheet1", wb.Worksheet(1).Name);
+            Assert.AreEqual("Sheet2", wb.Worksheet(2).Name);
+            Assert.AreEqual("Sheet3", wb.Worksheet(3).Name);
+        }
+
+        [TestMethod]
+        public void InsertingSheets2()
+        {
+            var wb = new XLWorkbook();
+            wb.Worksheets.Add("Sheet2");
+            wb.Worksheets.Add("Sheet1", 1);
+            wb.Worksheets.Add("Sheet3");
+
+            Assert.AreEqual("Sheet1", wb.Worksheet(1).Name);
+            Assert.AreEqual("Sheet2", wb.Worksheet(2).Name);
+            Assert.AreEqual("Sheet3", wb.Worksheet(3).Name);
+        }
+
+        [TestMethod]
+        public void InsertingSheets3()
+        {
+            var wb = new XLWorkbook();
+            wb.Worksheets.Add("Sheet3");
+            wb.Worksheets.Add("Sheet2", 1);
+            wb.Worksheets.Add("Sheet1", 1);
+            
+
+            Assert.AreEqual("Sheet1", wb.Worksheet(1).Name);
+            Assert.AreEqual("Sheet2", wb.Worksheet(2).Name);
+            Assert.AreEqual("Sheet3", wb.Worksheet(3).Name);
+        }
+
+        [TestMethod]
+        public void DeletingSheets1()
+        {
+            var wb = new XLWorkbook();
+            wb.Worksheets.Add("Sheet3");
+            wb.Worksheets.Add("Sheet2");
+            wb.Worksheets.Add("Sheet1", 1);
+
+            wb.Worksheet("Sheet3").Delete();
+
+            Assert.AreEqual("Sheet1", wb.Worksheet(1).Name);
+            Assert.AreEqual("Sheet2", wb.Worksheet(2).Name);
+            Assert.AreEqual(2, wb.Worksheets.Count);
+        }
+        
     }
 }