This article casts a critical eye on the Simple Object Access Protocol, assessing the value this much-discussed new technology can provide developers and demonstrating its foundation in a mixture of the old RPC (remote procedure calls) technology and in XML. It examines RPC, XML-RPC, RMI, and SOAP in detail, comparing and contrasting the use of each, and discusses whether SOAP makes sense. This article also includes sample code for a SOAP envelope.