The specific implications of the patient care motives of health care staff are considered for the relationship between experiences with co-workers and attitudinal criteria. Personal attitudes toward co-workers (member attraction) and perceptions of strain among co-workers (group fragmentation) are found to be significantly related to intrinsic reward satisfaction and propensity to leave. The implications of individual differences are addressed by considering the moderating effects that internal-external control orientation and need for achievement have on the relationship between work group variables and work attitudes. Modest evidence is found that member attraction is more highly related to work attitudes for externals than for internals. Work group experiences are also found to be more highly related to work attitudes for technicians, aides, and orderlies, who have a low need for achievement than for others in this staff group. High need for achievement is found to be associated with high intrinsic reward satisfaction and low propensity to leave for both staff groups. It is cautioned that these findings may not generalize to many non-health-care settings. It is suggested that hospital supervisors should be sensitive to differences among individuals' responses to group pressures and stresses, even when precise personality measures are not available to them.