The current chapter discusses on the effectiveness of team training in providing patient safety. Although evaluations do exist at this level, evidence is mixed and a clear picture of this level of training effectiveness is not achievable at this time. Although the results of most studies are encouraging, other studies have shown non significant effects. For example, the MedTeams Labor and Delivery training resulted in no statistically significant differences between the intervention and control groups, or between any individual outcomes or most of the clinical process or outcome measures. Overall, although few medical team training program (MTT) evaluations have successfully assessed the impact of team training on organizational outcomes, the available evidence suggests that teamwork positively impacts patient outcomes. Nevertheless, better and more robust evaluations of MTT programs are required.