This tutorial presents the foundational knowledge for the researchers and practitioners on Service- Oriented Architecture (SOA) and Web services. The traditional ?triangle? SOA and variations that better support SOA services and solutions will be examined. Critical Web services infrastructures will be covered, such as WSDL, BPEL, WSRF, Discovery, Composition, Registry, and Web services invocation and relationship binding. How Web 2.0 and SOA can benefit with each other will also be explored. An IEEE SOA Solution Reference Architecture standardization initiative will be introduced in this tutorial to illustrate how different pieces of technology components can be used to build reusable, flexible, and extensible SOA solutions. Finally, the presenter will depict research and development challenges and directions in the field of SOA and Web services. The target audiences are all-level researchers, practitioners, and students. This tutorial material is created for the IEEE Body of Knowledge initiative on Services Computing, which is sponsored by the IEEE Computer Society Technical Committee on Services Computing.