The purpose of this study was to determine whether the teams that received interpersonal training would function more effectively as a team than the teams that did not receive training. Individuals from a large division of a major defense contractor in the southern part of the United States served as subjects. Data were collected using the Team Effectiveness Profile designed to measure team effectiveness. This survey measures the overall score as well as five sub-scores. It was hypothesized that the teams that received training would function more effectively than the teams that did not receive training. The hypotheses were not supported. Results were explained, among other things, by the internal and external changes that hampered the transition towards self-managed work teams.