A team is a group of people who come together to achieve a purpose. Teams are organic - they grow and change - and by teaching how teams work we can help team members to understand each other and learn how to work together more effectively. When asked to describe who we are, most of us talk about the groups to which we belong. Tennis club, bowling league, church choir, etc. Members have a sense of shared purpose, and therefore a shared identity and a shared language. Creating a change to a team, such as implementing Lean principles, requires careful consideration and respect for this identity.