The trick with team building is to transfer what is "learned" into action once team members return to the workplace. This is an essential piece of any team building activity.
Small Group Discussion
Ideal Group Size
Probably not more than 10-15 people, so ideal for smaller teams.
Time For Exercise
10-15 minutes at the end
Detailed Instructions If Needed
Ideally arrange people in a circie or semi-circle.
Ask each person in turn to come up with at least one commitment they can make to the rest of the group on what they will do to be a better teammate at work. Give the group a short time to think. Then have each person share their commitment.
Additional Information if Available
It's a good idea, in the early part of the team building session, as part of the introduction to tell people right up front they will be asked to make that commitment. Remind them through out the seminar/day.