Abstract
To better understand the nature of joint expertise and its underlying processes, we need not only analyses of the general conditions for skilled group action, but also descriptive accounts of the features and dimensions that vary across distinct performances and contexts, such as sport and the arts. And in addition to positioning our accounts against current models of individual skill, we need concepts and lessons from work on collaborative processes in other cognitive domains. This paper examines ecological or situational components of expert joint action in practice, then offers a selective survey of some key cognitive and affective resources that shape and transform group performance.