The purpose of this study was to test a motivational model of sport dropout that integrates the four-stage causal sequence proposed by the Hierarchical Model of Vallerand (1997) and elements from achievement goal theory (Nicholls, 1989). The model posits that a task involving motivational climate facilitates, while an ego-involving climate undermines, perceptions of competence, autonomy, and relatedness. In turn, feeling incompetent, non-autonomous, and unrelated to others undermines self-determined motivation toward handball which leads to the intention of dropping out of the game. Finally, such intentions are implemented later. Three hundred and thirty-five female handballers completed a motivation questionnaire and were followed for 21 months. In France, as in many Western countries, an increasing number of people engage in sport (see for example, Ewing & Seefeldt, 1996;Russell, Allen, & Wilson, 1996;Wankel & Mummery, 1996). In 1997, 14 million individuals were registered in French sporting federations (Data of the Ministry for Youth and Sports, 1997). However, this massive passion for sport masks a paradox: a massive number of teenagers, particularly girls, drop out from sport every year (Gould, 1987;Russell al., 1996;Sallis & Patrick, 1996;Wankel & Mummery, 1996). For example, 50% of French women handball players drop out between 13 and 15 years of age (Guillet & Sarrazin, 1999, unpublished data, University of Grenoble, France). Given the multiple benefits of the regular practice of physical activity revealed in many studies (see Martinsen & Stephens, 1994, for a review), it is unfortunate that a large number of children and teenagers terminate their participation in a physical activity. Moreover, some experts identified adolescents as a group 'at risk' due to declining physical activity and subsequent health-related behaviour and outcomes (Sallis & Patrick, 1996). If the goal is to increase the physical activity level of the teenage population, more research is needed with regard to factors related to their physical activity. A key variable to look at when attempting to predict sport participation is motivation (Vallerand, Deci, & Ryan, 1987;Vallerand & Losier, 1999;Vallerand & Rousseau, 2001). 'Motivation represents the hypothetical construct used to describe the internal and/or external forces that produce the initiation, direction, intensity, and persistence of behaviour ' (Vallerand & Thill, 1993, p. 18, translated by the authors). Various motivational theories can be useful with respect to the study of sport dropout (see Gould, 1987;Weiss & Chaumeton, 1992;Sarrazin & Guillet, 2001, for reviews). However, a model that seems particularly well suited to study the dropout issue is the Hierarchical Model of Intrinsic and Extrinsic Motivation (HMIEM, Vallerand, 1997; Vallerand & Ratelle, in press). Drawing its roots in self-determination theory , 1991, the HMIEM model has furthered our understanding of motivational processes involved in the dropout issue in education (Vallerand, Fortier, & Guay, 1997...