I was having a conversation with one of my colleagues and we were having a debate related to what Web Service technologies made sense to use for one of our new projects. After doing some digging I was surprised to find out that ASMX 2.0 is only compliance with SOAP and WSDL Specifications. The below graph is an extract from a document supplied by Microsoft (click for the full view). Digging deeper I learned that ASMX had many of the bones required to become compliant with the other standards, assuming you were willing to write the code. After a little sole searching and some prototyping with other technologies I decided that; while not compliant; Microsoft had one feature that made it all worth while. It was FAST, EASY, FAST, and EASY... and given the inherent support within TFS we opted to go with ASMX. That being said, you should look closely at ASMX compliance levels, WSE, WCF, etc... before making any decisions on what to use.