In this article, we present a reconceptualization of sport as a series of collaborative contests with players on different teams scoring goals cooperatively: players on both sides lose or both sides win together depending on whether they can improve the scores they earn in overcoming limitations and obstacles by working with the other team. When teams play multiple rounds of a contest that measures their performance as collaborators attempting to improve relative to an objective standard of excellence, sport gives players experience measuring positive interdependence between teams. To illustrate the potential impact on moral development, we contrast two versions of one sport (volleyball) and analyze the character development implications of using collaborative sport to develop moral behavior. We contend that both traditional win-lose sports and collaborative sports (that keep score on a win-win-or-lose-lose basis) tend to develop positive -- but different -- character attributes. Examples from two programs give preliminary evidence that collaborative sport helps to strengthen moral behavior, but more thorough research is needed.