NRSG - Effective Groups/Teams

We have all worked in group or teams for one purpose or another. For a school project. In a workplace setting where a problem has arisen which has created a need for change. As a member of a sports team trying to create strategies to win. Despite the fact that each individual is unique and possess their own strengths that contribute to effective groups or teams, some similarities do exist. Perhaps it's ambition or a vision of a common goal? What do you think are some individual characteristics that help to make a group or team effective, productive, or successful?