As team projects become ever more common in business and in the marketing classroom, an increased understanding of factors contributing to team effectiveness is necessary for instructors to assist students in realizing the potential benefits of this pedagogical tool. Drawing from a wide base of literature on team research, the authors develop an input-process-output model of team effectiveness. Using data from 85 teams from marketing classes, this model was tested. Results support the positive and direct role of cohesion as an input variable on the process variable of team work. Additional relationships are explored, and the implications of the research findings are discussed with practical suggestions for the marketing classroom. © 2002, Sage Publications. All rights reserved.