title: Web Service Versioning - Adding Operations to a Service Contract in WCF
body: <p>In a WCF service, what happens if I add methods as operation contracts after clients (that consume the service) have completed their implementations? Will the existing clients have to modify their implementations even though they do not use the new operation contract methods?</p>
  
  <p>EDIT: Will the clients have to update their proxy even though they don't use the new contracts? </p>