The concepts of "learning community" and "community of practice" may hold value to researchers, but questions exist as to how well they help in organizing and clarifying the type of critical thinking involved in investigative work. This paper approaches the problem from two directions. One is to deconstruct the two concepts themselves and explore their range of meanings. The other is to explore more grounded research questions about learning and the conditions for learning that are relevant to researching learning communities and/or communities of practice. The purpose of this investigation is to develop criteria by which one can judge whether these two ideas provide useful frameworks for organizing questions involving learning communities and communities of practice. The discussion includes asking what kind of empirical evidence is needed to recognize such communities when perceived, and what kind of learning is occurring, how it is taking place, and what the factors are that affect its magnitude and direction(s). If these concepts do not provide added value to researchers, then it is possible that they may provide the route to yet other theories that provide greater purchase on the problems of facilitating learning in a wide range of contexts. (RT)