Culture can mean several things when referring to a group: identity, values, goals, principles. Culture can be defined from the inside or outside – how is your group viewed by others, either at your institution or outside? Is your group viewed as “functional,” in which the members get along with each other, work as a team, and accomplish important goals? Or does it carry a reputation of being a “difficult place to work”? Usually a culture is a mix, some elements hardworking and driven, some supportive and nurturing. This chapter talks directly about how to develop a positive culture for your group, and how to be explicit in the process. It starts with recognizing and acknowledging the elements of your core identity as a group – what are your guiding values and behaviors? It dives into the difference between acceptable behaviors that can stimulate the group and be positively provocative, versus those that can be negative, destructive, and unacceptable, and how to deal with them when they occur. It describes the principle of accountability and how all group members are responsible for the overall health of the group. It discusses how to handle difficult interpersonal interactions once they’ve taken place, and how to reset the team after a negative culture event. It reminds the reader of the importance of embracing diversity, that differing opinions are necessary and important, but negativity and destructive behavior is never helpful.