Service Oriented Architecture (SOA) is an emerging paradigm for orchestrating software components to build new composite applications that enable businesses, government agencies and other organizations to collaborate across institutional boundaries. SOA offers new languages and a variety of software development tools that enable software engineers to configure software as services and to interconnect services with other services independent of differences in operating platform and programming and communicating languages. However, SOA composite applications introduce additional complexity into the construction, deployment and maintenance of software, for the purpose of aggravating the issue of program comprehension, which is at the heart of software maintenance. This article describes the challenges in SOA program comprehension and reports on the results of a two-part case study aimed at identifying information that would help a SOA software maintainer. Analysis of the results indicates a need for higher-level abstractions and visualizations that can enhance conventional text-based search to support SOA program understanding. This paper then reports on several specific abstractions, visualization methods, and the development of an intelligent search tool to enhance comprehension of the relationships and data within a SOA composite application.