As the 100-year anniversary of the Flexner Report approaches us, the physician workforce in the 21st century faces a radically different health care environment. To function effectively in this environment, future physicians, including medical students, will need educational programs that incorporate the theory and practice of teams and teamwork. Medical school graduates will be expected to understand how teams function and be capable themselves of functioning in a team. They will need to be competent in the knowledge, skills, and attitudes of teams and teamwork. Numerous reports during the past 10 years from national oversight and safety institutes and agencies have supported the need for team training in the health care environment, especially as a means to decrease errors and increase patient safety. Hospital training programs have begun implementing interdisciplinary team training around high-risk scenarios for their trainees and staff. However, for most medical schools, competence in team training has not been an instructional objective of educating medical students. Most instruction has been individual learning (i.e., lectures) or group learning (i.e., team-based or problem-based learning) even though there is strong evidence for team learning to be effective. With the ongoing changes in health care, it is argued that Flexner would concur that team training is necessary for medical students.