Unfortunately it's not quite that simple.
Since m_strSyncLockSave is set to the literal "Save", it will refer to an
intened string, and all instances will actually point to the same object.

To fix this always use a "new Object" for syncronization instead of a
string.

Like this:

Public Class StringLock
 Private m_SyncLockSave As new object

Here's a sample.

David

Public Class StringLock

 Private m_strSyncLockSave As String = "Save"

 Public Sub Save()

   SyncLock m_strSyncLockSave
     System.Threading.Thread.Sleep(1000 * 5)
     Console.WriteLine(AppDomain.GetCurrentThreadId & " " & Now)
   End SyncLock

 End Sub

End Class

Module Module1

 Sub Main()
   Dim s1 As New StringLock
   Dim s2 As New StringLock
   Dim t1 As New Threading.Thread(AddressOf s1.Save)
   Dim t2 As New Threading.Thread(AddressOf s2.Save)
   t1.Start()
   t2.Start()
   t1.Join()
   t2.Join()

 End Sub

End Module