To better understand the principles at work in team sports, a pertinent approach could be to model the interactions between the players and the environment as a complex system. In team sports, environmental variables represent fluctuating conditions that momentarily constrain the organization of players’ actions (Ali & Farraly, 1990; Bouthier, 1989; Caron & Pelchat, 1975; David, 1993; Davids, Hanford, & Williams, 1994; Gréhaigne, 1988; Gréhaigne & Godbout, 1995; Walliser, 1977). For example, according to the available space, the ball carrier’s choices will dictate the success of an attack. In order to better understand such choices, this chapter examines, in the first part, the systemic nature of team sport. The second part presents a French analysis model based on the oppositional relationship.