Know what they call someone without a team? A lone visionary. Or a lone crusader. Or any of a number of other things, generally preceded by the word lone. What you won't hear the public call such an individual is a leader. A leader by definition needs someone to lead, and an effective leader must know how to build a team. What you need to do will depend completely on the people you work with and your specific circumstances. However, there are various principles and techniques that can be helpful.