Cromwell and Peterson's goal of introducing quantitative testing into family assessment and therapy is laudable; the system they propose--the Multisystem-Multimethod (MS-MM) approach is not. MS-MM is confusing, deceptive, and misleading for clinicians who want to use tests to sharpen their diagnostic assessments and predictions. What is needed is specific theory linking various family processes and individual behaviors, as well as equally specific information about the reliability and validity of the tests. Likewise, the MS-MM approach is completely inadequate for clinicians seeking to use tests to enlarge their clinical imaginations. What is needed is a more down-to-earth examination of the influence of testing on the family therapy system.