Knowledge-rich contexts express conceptual information for a term. Terminographers need such contexts to construct definitions, and to acquire domain knowledge. This paper summarizes what we have learned about extracting knowledge-rich contexts semi-automatically. First, we define what we mean by a knowledge-rich context. Second, we describe the tools and methods we have developed at the University of Ottawa for extracting knowledge-rich contexts. We conclude with a discussion of the potential and the problems of this technology.