With the SOA (Service Oriented Architecture) wave catching up in the industry, Microsoft has over the last few years developed several technologies for implementing SOA. There was a need to unify the existing technologies into a single unified model. With the introduction of Windows Communication Foundation (WCF), Microsoft has now come up with a new framework that unifies several existing models into a single coherent programming model to develop applications based on SOA. WCF is a set of .NET technologies for building and running connected systems. In this article Poornachandra Sarang will provide an overview of this new framework and walk through the construction of a service and a client. He will also discuss several of the benefits offered by WCF.