The commentary has greatly enriched the discussion initiated by the three target articles. The distinction between constructs and concepts contributes to both the top-down and bottom-up aspects of the dialectic between measurement theory and practice. The distinction also illuminates the abstraction from observation to manifest variables. However, the semantic analysis of variables in terms of ordered pairs of individuals and values of variables does not seek to describe a procedure for defining constructs as part of the test development process. As such, uncertainty about population membership does not pose a pragmatic constraint on the application of the distinction between concepts and constructs. Finally, meaning and reference in the context of test development can best be understood as jointly determined by both how the world is and the nature of the vocabularies chosen to describe it. Thus, both of these factors bear on the definition of specific constructs and concepts measured by individual tests. Distinguishing constructs from concepts can help clarify and advance discourse on testing and measurement across a wide range of domains. (Contains 1 footnote.)