diff --git a/src/Umbraco.Core/StringExtensions.cs b/src/Umbraco.Core/StringExtensions.cs
index 03b21cfc0c..8d4883a6fc 100644
--- a/src/Umbraco.Core/StringExtensions.cs
+++ b/src/Umbraco.Core/StringExtensions.cs
@@ -23,7 +23,9 @@ namespace Umbraco.Core
     ///</summary>
     public static class StringExtensions
     {
+        [UmbracoWillObsolete("Do not use this constants. See IShortStringHelper.CleanStringForSafeAliasJavaScriptCode.")]
         public const string UmbracoValidAliasCharacters = "_-abcdefghijklmnopqrstuvwxyz1234567890";
+        [UmbracoWillObsolete("Do not use this constants. See IShortStringHelper.CleanStringForSafeAliasJavaScriptCode.")]
         public const string UmbracoInvalidFirstCharacters = "01234567890";
 
 		/// <summary>
diff --git a/src/Umbraco.Core/Strings/DefaultShortStringHelper.cs b/src/Umbraco.Core/Strings/DefaultShortStringHelper.cs
index a3fd8f7ec1..16aa05d1a0 100644
--- a/src/Umbraco.Core/Strings/DefaultShortStringHelper.cs
+++ b/src/Umbraco.Core/Strings/DefaultShortStringHelper.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Globalization;
+using Umbraco.Core.Configuration;
 
 namespace Umbraco.Core.Strings
 {
@@ -133,6 +134,65 @@ namespace Umbraco.Core.Strings
 
         #endregion
 
+        #region JavaScript
+
+        const string CsfaJsValidCharacters = "_abcdefghijklmnopqrstuvwxyz1234567890";
+        const string CsfaJsInvalidFirstCharacters = "01234567890_";
+
+        private const string CsfsaJsFormat = @"
+var UMBRACO_FORCE_SAFE_ALIAS = {0};
+var UMBRACO_FORCE_SAFE_ALIAS_VALIDCHARS = '{1}';
+var UMBRACO_FORCE_SAFE_ALIAS_INVALID_FIRST_CHARS = '{2}';
+
+function safeAlias(alias) {{
+    if (UMBRACO_FORCE_SAFE_ALIAS) {{
+        var safeAlias = '';
+        var aliasLength = alias.length;
+        for (var i = 0; i < aliasLength; i++) {{
+            currentChar = alias.substring(i, i + 1);
+            if (UMBRACO_FORCE_SAFE_ALIAS_VALIDCHARS.indexOf(currentChar.toLowerCase()) > -1) {{
+                // check for camel (if previous character is a space, we'll upper case the current one
+                if (safeAlias == '' && UMBRACO_FORCE_SAFE_ALIAS_INVALID_FIRST_CHARS.indexOf(currentChar.toLowerCase()) > 0) {{ 
+                    currentChar = '';
+                }} else {{
+                    // first char should always be lowercase (camel style)
+                    if (safeAlias.length == 0)
+                        currentChar = currentChar.toLowerCase();
+
+                    if (i < aliasLength - 1 && safeAlias != '' && alias.substring(i - 1, i) == ' ')
+                        currentChar = currentChar.toUpperCase();
+
+                    safeAlias += currentChar;
+                }}
+            }}
+        }}
+
+        return safeAlias;
+
+    }} else {{
+        return alias;
+    }}
+}}
+
+function isSafeAlias(alias) {{
+    return alias == safeAlias(alias);
+}}
+";
+
+        /// <summary>
+        /// Gets the JavaScript code defining functions safeAlias(alias) and isSafeAlias(alias).
+        /// </summary>
+        public string CleanStringForSafeAliasJavaScriptCode
+        {
+            get
+            {
+                return string.Format(CsfsaJsFormat,
+                    UmbracoSettings.ForceSafeAliases ? "true" : "false", CsfaJsValidCharacters, CsfaJsInvalidFirstCharacters);
+            }
+        }
+
+        #endregion
+
         #region IShortStringHelper CleanFor...
 
         /// <summary>
diff --git a/src/Umbraco.Core/Strings/IShortStringHelper.cs b/src/Umbraco.Core/Strings/IShortStringHelper.cs
index 4ce03888e3..d98f14ac96 100644
--- a/src/Umbraco.Core/Strings/IShortStringHelper.cs
+++ b/src/Umbraco.Core/Strings/IShortStringHelper.cs
@@ -15,12 +15,20 @@ namespace Umbraco.Core.Strings
         /// <remarks>Will be called by <c>ShortStringHelperResolver</c> when resolution freezes.</remarks>
         void Freeze();
 
+        /// <summary>
+        /// Gets the JavaScript code defining functions safeAlias(alias) and isSafeAlias(alias).
+        /// </summary>
+        string CleanStringForSafeAliasJavaScriptCode { get; }
+
         /// <summary>
         /// Cleans a string to produce a string that can safely be used in an alias.
         /// </summary>
         /// <param name="text">The text to filter.</param>
         /// <returns>The safe alias.</returns>
-        /// <remarks>The string will be cleaned in the context of the IShortStringHelper default culture.</remarks>
+        /// <remarks>
+        /// <para>The string will be cleaned in the context of the IShortStringHelper default culture.</para>
+        /// <para>A safe alias is [a-z][a-zA-Z0-9_]* although legacy will also accept '-', and '_' at the beginning.</para>
+        /// </remarks>
         string CleanStringForSafeAlias(string text);
 
         /// <summary>
diff --git a/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs b/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs
index d278cf32e8..30367c176c 100644
--- a/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs
+++ b/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs
@@ -35,6 +35,65 @@ namespace Umbraco.Core.Strings
 
         #endregion
 
+        #region JavaScript
+
+        const string CsfaJsValidCharacters = "_-abcdefghijklmnopqrstuvwxyz1234567890";
+        const string CsfaJsInvalidFirstCharacters = "01234567890";
+
+        private const string CsfsaJsFormat = @"
+var UMBRACO_FORCE_SAFE_ALIAS = {0};
+var UMBRACO_FORCE_SAFE_ALIAS_VALIDCHARS = '{1}';
+var UMBRACO_FORCE_SAFE_ALIAS_INVALID_FIRST_CHARS = '{2}';
+
+function safeAlias(alias) {{
+    if (UMBRACO_FORCE_SAFE_ALIAS) {{
+        var safeAlias = '';
+        var aliasLength = alias.length;
+        for (var i = 0; i < aliasLength; i++) {{
+            currentChar = alias.substring(i, i + 1);
+            if (UMBRACO_FORCE_SAFE_ALIAS_VALIDCHARS.indexOf(currentChar.toLowerCase()) > -1) {{
+                // check for camel (if previous character is a space, we'll upper case the current one
+                if (safeAlias == '' && UMBRACO_FORCE_SAFE_ALIAS_INVALID_FIRST_CHARS.indexOf(currentChar.toLowerCase()) > 0) {{ 
+                    currentChar = '';
+                }} else {{
+                    // first char should always be lowercase (camel style)
+                    if (safeAlias.length == 0)
+                        currentChar = currentChar.toLowerCase();
+
+                    if (i < aliasLength - 1 && safeAlias != '' && alias.substring(i - 1, i) == ' ')
+                        currentChar = currentChar.toUpperCase();
+
+                    safeAlias += currentChar;
+                }}
+            }}
+        }}
+
+        return safeAlias;
+
+    }} else {{
+        return alias;
+    }}
+}}
+
+function isSafeAlias(alias) {{
+    return alias == safeAlias(alias);
+}}
+";
+
+        /// <summary>
+        /// Gets the JavaScript code defining functions safeAlias(alias) and isSafeAlias(alias).
+        /// </summary>
+        public string CleanStringForSafeAliasJavaScriptCode
+        {
+            get
+            {
+                return string.Format(CsfsaJsFormat,
+                    UmbracoSettings.ForceSafeAliases ? "true" : "false", CsfaJsValidCharacters, CsfaJsInvalidFirstCharacters);
+            }
+        }
+
+        #endregion
+
         #region IShortStringHelper CleanFor...
 
         /// <summary>
diff --git a/src/Umbraco.Core/Strings/Notes.txt b/src/Umbraco.Core/Strings/Notes.txt
new file mode 100644
index 0000000000..b1f82636cd
--- /dev/null
+++ b/src/Umbraco.Core/Strings/Notes.txt
@@ -0,0 +1,40 @@
+Two constants are defined in StringExtensions:
+UmbracoValidAliasCharacters
+UmbracoInvalidFirstCharacters
+
+They were used exclusively by umbraco/js/UmbracoCasingRules.aspx.cs to define some JavaScript variables
+which in turn were used by genericProperty.js to provide validation for aliases.
+
+UmbracoCasingRules.aspx and genericProperty.js are used in:
+  Umbraco.Web\umbraco.presentation\umbraco\controls\ContentTypeControlNew.ascx
+  Umbraco.Web\umbraco.presentation\umbraco\controls\GenericProperties\GenericProperty.ascx
+
+genericProperty.js defined the following functions:
+  safeAlias(alias) : provides a safe alias version of alias
+  isValidAlias(alias) : whether an alias is safe
+  checkAlias(id) : plugs a safe alias validator / corrector on an element
+  duplicatePropertyNameAsSafeAlias(propertyId, aliasId) : creates the alias from the prop. name
+
+These are used to validate the alias of the content type, and of properties. No other alias in
+Umbraco back-end seem to be validated in UI at that point. And, there seem to be no server-side
+validation so the server just seems trust the UI.
+
+Whereas in theory, we should only accept that the casing required by the user is different
+from what our "toSafeAlias" method would provide, anything else is a validation error.
+
+Legacy safe aliases accept leading and trailing dashes and underscores.
+
+REFACTOR
+
+Abstract string methods into IShortStringHelper, and create a new DefaultShortStringHelper which
+re-implements methods in a clean nice way. The new aliases do not accepts dashes, nor leading
+underscores.
+
+Entirely refactor StringExtensions to rely on IShortStringHelper (via a resolver).
+
+The constants in StringExtensions should go, but we keep them for backward compatility.
+The legacy helper is 100% backward compatible even at JavaScript level, but the new helper
+is NOT, it does server-side validation of aliases, all sorts of things, using an api service.
+
+UmbracoCasingRules.aspx.cs is _gone_ in all cases, replaced by the JavaScript served by
+the api service.
diff --git a/src/Umbraco.Core/Umbraco.Core.csproj b/src/Umbraco.Core/Umbraco.Core.csproj
index 675ee57f4d..1bde2f8857 100644
--- a/src/Umbraco.Core/Umbraco.Core.csproj
+++ b/src/Umbraco.Core/Umbraco.Core.csproj
@@ -751,7 +751,9 @@
       <Name>umbraco.interfaces</Name>
     </ProjectReference>
   </ItemGroup>
-  <ItemGroup />
+  <ItemGroup>
+    <Content Include="Strings\Notes.txt" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$(SolutionDir)\.nuget\nuget.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
diff --git a/src/Umbraco.Tests/CoreStrings/MockShortStringHelper.cs b/src/Umbraco.Tests/CoreStrings/MockShortStringHelper.cs
index f8256c5006..3773f316a2 100644
--- a/src/Umbraco.Tests/CoreStrings/MockShortStringHelper.cs
+++ b/src/Umbraco.Tests/CoreStrings/MockShortStringHelper.cs
@@ -12,6 +12,8 @@ namespace Umbraco.Tests.CoreStrings
 
         public bool IsFrozen { get; private set; }
 
+        public string CleanStringForSafeAliasJavaScriptCode { get { return "CSFSAJS"; } }
+
         public string CleanStringForSafeAlias(string text)
         {
             return "SAFE-ALIAS::" + text;
diff --git a/src/Umbraco.Web.UI/umbraco/controls/ContentTypeControlNew.ascx b/src/Umbraco.Web.UI/umbraco/controls/ContentTypeControlNew.ascx
index a2f8735faa..2a0af303c9 100644
--- a/src/Umbraco.Web.UI/umbraco/controls/ContentTypeControlNew.ascx
+++ b/src/Umbraco.Web.UI/umbraco/controls/ContentTypeControlNew.ascx
@@ -106,10 +106,9 @@
       </div>
     </cc2:Pane>
 </asp:Panel>
+<%-- cannot put a <%= block here 'cos it prevents the Controls collection from being modified = use a literal --%>
 <script type="text/javascript">
     $(function () {
-        var mailControlId = '<asp:Literal id="theClientId" runat="server"/>';
-        duplicatePropertyNameAsSafeAlias(mailControlId + '_GenericPropertyNew_control_tbName', mailControlId + '_GenericPropertyNew_control_tbAlias');
-        checkAlias(mailControlId + '_GenericPropertyNew_control_txtAlias');
+        <asp:Literal runat="server" ID="checkTxtAliasJs" />
     });
 </script>
\ No newline at end of file
diff --git a/src/Umbraco.Web.UI/umbraco/controls/GenericProperties/GenericProperty.ascx b/src/Umbraco.Web.UI/umbraco/controls/GenericProperties/GenericProperty.ascx
index d85224792a..64cace4a38 100644
--- a/src/Umbraco.Web.UI/umbraco/controls/GenericProperties/GenericProperty.ascx
+++ b/src/Umbraco.Web.UI/umbraco/controls/GenericProperties/GenericProperty.ascx
@@ -61,5 +61,8 @@
 		</div>
 </li>
 <script type="text/javascript">
-    $(function() { checkAlias('<%=this.ClientID%>_tbAlias'); });
+    $(function() {
+        checkAlias('<%=tbAlias.ClientID%>');
+        duplicatePropertyNameAsSafeAlias('<%=tbName.ClientID%>', '<%=tbAlias.ClientID%>')
+    });
 </script>
\ No newline at end of file
diff --git a/src/Umbraco.Web.UI/umbraco_client/GenericProperty/genericProperty.js b/src/Umbraco.Web.UI/umbraco_client/GenericProperty/genericProperty.js
index e51f628d52..9554fa6f90 100644
--- a/src/Umbraco.Web.UI/umbraco_client/GenericProperty/genericProperty.js
+++ b/src/Umbraco.Web.UI/umbraco_client/GenericProperty/genericProperty.js
@@ -16,53 +16,25 @@ function duplicatePropertyNameAsSafeAlias(theId, theAliasId) {
     jQuery('#' + theId).keyup(function(event) {
         var message = jQuery('#' + theId).val();
         jQuery('#' + theAliasId).val(safeAlias(message));
-    })
+    });
 }
 
 function checkAlias(theId) {
     jQuery('#' + theId).keyup(function(event) {
         var currentAlias = jQuery('#' + theId).val();
-        jQuery('#' + theId).toggleClass('aliasValidationError', !isValidAlias(currentAlias));
-    })
+        jQuery('#' + theId).toggleClass('aliasValidationError', !isSafeAlias(currentAlias));
+    });
 
     jQuery('#' + theId).blur(function(event) {
         var currentAlias = jQuery('#' + theId).val();
         jQuery('#' + theId).val(safeAlias(currentAlias));
         jQuery('#' + theId).removeClass('aliasValidationError');
-    })
-
+    });
 }
 
-function safeAlias(alias) {
-    if (UMBRACO_FORCE_SAFE_ALIAS) {
-        var safeAlias = '';
-        var aliasLength = alias.length;
-        for (var i = 0; i < aliasLength; i++) {
-            currentChar = alias.substring(i, i + 1);
-            if (UMBRACO_FORCE_SAFE_ALIAS_VALIDCHARS.indexOf(currentChar.toLowerCase()) > -1) {
-                // check for camel (if previous character is a space, we'll upper case the current one
-                if (safeAlias == '' && UMBRACO_FORCE_SAFE_ALIAS_INVALID_FIRST_CHARS.indexOf(currentChar.toLowerCase()) > 0) { 
-                    currentChar = '';
-                } else {
-                    // first char should always be lowercase (camel style)
-                    if (safeAlias.length == 0)
-                        currentChar = currentChar.toLowerCase();
-
-                    if (i < aliasLength - 1 && safeAlias != '' && alias.substring(i - 1, i) == ' ')
-                        currentChar = currentChar.toUpperCase();
-
-                    safeAlias += currentChar;
-                }
-            }
-        }
-
-        return safeAlias;
-
-    } else {
-        return alias;
-    }
-}
+// note: safeAlias(alias) and isSafeAlias(alias) now defined by UmbracoCasingRules.aspx along with constants
 
+// provided for backward-compatibility, should anybody non-core be using it
 function isValidAlias(alias) {
-    return alias == safeAlias(alias);
+    return isSafeAlias(alias);
 }
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx
index a2f8735faa..2a0af303c9 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx
@@ -106,10 +106,9 @@
       </div>
     </cc2:Pane>
 </asp:Panel>
+<%-- cannot put a <%= block here 'cos it prevents the Controls collection from being modified = use a literal --%>
 <script type="text/javascript">
     $(function () {
-        var mailControlId = '<asp:Literal id="theClientId" runat="server"/>';
-        duplicatePropertyNameAsSafeAlias(mailControlId + '_GenericPropertyNew_control_tbName', mailControlId + '_GenericPropertyNew_control_tbAlias');
-        checkAlias(mailControlId + '_GenericPropertyNew_control_txtAlias');
+        <asp:Literal runat="server" ID="checkTxtAliasJs" />
     });
 </script>
\ No newline at end of file
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.cs b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.cs
index c612a39180..49dd332d09 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.cs
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.cs
@@ -113,7 +113,7 @@ namespace umbraco.controls
                 PanePropertiesInherited.Visible = true;
             }
 
-            theClientId.Text = this.ClientID;
+            checkTxtAliasJs.Text = string.Format("checkAlias('{0}');", txtAlias.ClientID);
         }
 
         protected void save_click(object sender, System.Web.UI.ImageClickEventArgs e)
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.designer.cs b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.designer.cs
index 320848521d..0bbd56ebbd 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.designer.cs
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/ContentTypeControlNew.ascx.designer.cs
@@ -364,12 +364,12 @@ namespace umbraco.controls {
         protected global::System.Web.UI.WebControls.PlaceHolder PropertyTypes;
         
         /// <summary>
-        /// theClientId control.
+        /// checkTxtAliasJs control.
         /// </summary>
         /// <remarks>
         /// Auto-generated field.
         /// To modify move field declaration from designer file to code-behind file.
         /// </remarks>
-        protected global::System.Web.UI.WebControls.Literal theClientId;
+        protected global::System.Web.UI.WebControls.Literal checkTxtAliasJs;
     }
 }
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx
index d85224792a..64cace4a38 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx
@@ -61,5 +61,8 @@
 		</div>
 </li>
 <script type="text/javascript">
-    $(function() { checkAlias('<%=this.ClientID%>_tbAlias'); });
+    $(function() {
+        checkAlias('<%=tbAlias.ClientID%>');
+        duplicatePropertyNameAsSafeAlias('<%=tbName.ClientID%>', '<%=tbAlias.ClientID%>')
+    });
 </script>
\ No newline at end of file
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx.designer.cs b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx.designer.cs
index db7127ceb9..6821d6c3a3 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx.designer.cs
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/controls/GenericProperties/GenericProperty.ascx.designer.cs
@@ -1,10 +1,9 @@
 //------------------------------------------------------------------------------
 // <auto-generated>
 //     This code was generated by a tool.
-//     Runtime Version:2.0.50727.4927
 //
 //     Changes to this file may cause incorrect behavior and will be lost if
-//     the code is regenerated.
+//     the code is regenerated. 
 // </auto-generated>
 //------------------------------------------------------------------------------
 
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/js/UmbracoCasingRules.aspx.cs b/src/Umbraco.Web/umbraco.presentation/umbraco/js/UmbracoCasingRules.aspx.cs
index e2b556ff7a..3fa91f1141 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/js/UmbracoCasingRules.aspx.cs
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/js/UmbracoCasingRules.aspx.cs
@@ -5,6 +5,7 @@ using System.Web;
 using System.Web.UI;
 using System.Web.UI.WebControls;
 using Umbraco.Core;
+using Umbraco.Core.Strings;
 using umbraco.cms.helpers;
 
 namespace umbraco.presentation.js
@@ -14,14 +15,8 @@ namespace umbraco.presentation.js
         protected void Page_Load(object sender, EventArgs e)
         {
             Response.ContentType = "text/javascript";
-            Response.Write(String.Format(@"
-var UMBRACO_FORCE_SAFE_ALIAS = {0};
-var UMBRACO_FORCE_SAFE_ALIAS_VALIDCHARS = '{1}';
-var UMBRACO_FORCE_SAFE_ALIAS_INVALID_FIRST_CHARS = '{2}';
-", UmbracoSettings.ForceSafeAliases.ToString().ToLower(), StringExtensions.UmbracoValidAliasCharacters, StringExtensions.UmbracoInvalidFirstCharacters));
-
+            // defines the constants _and_ provides code for safeAlias(alias) and isSafeAlias(alias)
+            Response.Write(ShortStringHelperResolver.Current.Helper.CleanStringForSafeAliasJavaScriptCode);
         }
-
-       
     }
 }