Popular teamwork assessments have been strongly criticized on the grounds of poor psychometric properties and their disconnect with conceptual models of teamwork. These issues raise concerns with respect to our ability to evaluate efforts devoted to advancing teamwork in academia. We report the development of a teamwork assessment that builds on empirically supported conceptualizations of team processes. Two studies were conducted to test and to cross-validate the psychometrics of the resulting measure. In the discussion section, we address the implications of our findings for conceptual models of teamwork and provide guidelines for using the measure in business education.