Interdisciplinary teams are important in providing care for older patients, but interdisciplinary teamwork is rarely a teaching focus, and little is known about trainees' attitudes towards it. To determine the attitudes of second-year post-graduate (PGY-2) internal medicine or family practice residents, advanced practice nursing (NP), and masters-level social work (MSW) students toward the value and efficiency of interdisciplinary teamwork and the physician's role on the team, a baseline survey was administered to 591 Geriatrics Interdisciplinary Team Training participants at eight U.S. academic medical centers from January 1997 to July 1999. Most students in each profession agreed that the interdisciplinary team approach benefits patients and is a productive use of time, but PGY-2s consistently rated their agreement lower than NP or MSW students. Interprofessional differences were greatest for beliefs about the physician's role; 73% of PGY-2s but only 44% to 47% of MSW and NP trainees agreed that a team's primary purpose was to assist physicians in achieving treatment goals for patients. Approximately 80% of PGY-2s but only 35% to 40% of MSW or NP trainees agreed that physicians have the right to alter patient care plans developed by the team. Although students from all three disciplines were positively inclined toward medical interdisciplinary teamwork, medical residents were the least so. Exposure to interdisciplinary teamwork may need to occur at an earlier point in medical training than residency. The question of who is ultimately responsible for the decisions of the team may be an "Achilles heel," interfering with shared decision-making.