Despite a robust body of practitioner-oriented literature focused on the importance of balancing customer demand with product supply within companies, there is very little empirical research suggesting how to achieve it. Sales and Operations Planning (S&OP) is a tactical approach meant to help firms accomplish demand and supply balance at aggregate levels. While guidebooks authored by consultants suggest best practices that lead to S&OP success, many experts agree that companies have fallen short of achieving the anticipated benefits. Carried out by cross-functional teams, S&OP entails getting people from different thought worlds to work toward a common goal, a challenging task for any company. Academia is still in the early stages of developing empirical pathways

predictive of S&OP performance. The purpose of this study is to test a model of S&OP performance grounded in group effectiveness theory. Using a survey-based approach, perspectives were captured from S&OP team members across a wide cross-section of industries representing sales and operations functions. The results of statistical analysis indicate that managers should focus on helping their teams to achieve a superordinate

identity. This allows team members to overcome functional biases and constructively engage in S&OP planning which in turn drives S&OP performance. Also of paramount importance are having team-based rewards and incentives that fully support overarching S&OP goals. These findings provide empirically-based guidance for managers seeking to determine which internal team and contextual support factors are most important for

S&OP success. Moreover, grounding S&OP in principles of group effectiveness theory within a broad framework will help support future academic study of S&OP and related efforts by firms to achieve demand and supply harmony.