Industrial and Organizational Psychology, 5 (2012), 2–24. Copyright  2012 Society for Industrial and Organizational Psychology. 1754-9426/12 FOCAL ARTICLE Teams Are Changing: Are Research and Practice Evolving Fast Enough? SCOTT I. TANNENBAUM Group for Organizational Effectiveness JOHN E. MATHIEU University of Connecticut EDUARDO SALAS University of Central Florida DEBRA COHEN Society for Human Resource Management Abstract In the past, there was a fairly strong alignment between what teams experienced, the topics that team researchers were studying, and the practices that organizations used to manage their teams. However, the nature of teams and the environment in which they operate has changed, and as a result, new needs have emerged. Although there have been some innovative advancements, research and practice have not always adjusted to remain aligned with emerging needs. We highlight 3 significant change themes that are affecting teams: (a) dynamic composition, (b) technology and distance, and (c) empowerment and delayering. For each theme, we share our observations, review the related science and identify future research needs, and specify challenges and recommendations for employing effective team-based practices in applied settings. We conclude with thoughts about the future and suggest that new theories, research methods, and analyses may be needed to study the new team dynamics. Teams have been an important part of organizational life for a long time. Orga- nizations use teams to tackle many of their most difficult and pressing needs. As such, researchers have studied team dynamics and have attempted to uncover how best to ensure team effectiveness. Much has been learned, and substantial progress has been made on the science and practice of team effectiveness in the past few decades. Yet, Correspondence concerning this article should be addressed to Scott I. Tannenbaum. E-mail: scott.tannenbaum@groupoe.com Address: Group for Organizational Effectiveness, Inc., 727 Waldens Pond Road, Albany, NY 12203. This research was partially supported by NASA Grant (#NNX11AR22G) awarded to The Group for Organizational Effectiveness, Inc. and NASA Grant (#NNX09AK48G) awarded to the University of Central Florida. we have reached a turning point for the study and application of teams. Tradition- ally, a team has been defined by certain characteristics. Consider, for example, two commonly cited definitions of teams: • Salas, Dickinson, Converse, and Tan- nenbaum (1992) defined a team as ‘‘a distinguishable set of two or more peo- ple who interact, dynamically, inter- dependently, and adaptively toward a common and valued goal/objective/ mission, who have each been assigned specific roles or functions to perform, and who have a limited life-span of membership’’ (p. 4). • Kozlowski and Bell (2003) defined teams as collectives ‘‘who exist to perform organizationally relevant 2