Norms are the rules that the team agrees to follow as it conducts its work. Norms may be written or may evolve as unwritten understandings over time. Most newly organizing teams find it effective to start out with an initial set of norms with the understanding that these will need to be reviewed and modified frequently. Some teams decide to review norms at the beginning or end of each meeting. The establishment and adherence to team norms helps build team discipline, trust between team members, and supports a safe environment.