Despite consensus recommendations the use of screening mammography remains low. We examined physician and patient related variables associated with requests to undergo screening mammography in a primary care setting, in order to assess current barriers to screening mammography at the level of the physician-patient interaction. A sample of 261 women over the age of 50, whose primary care was provided by resident physicians in a large, urban, academic medical center were examined. Data concerning patients and physicians demographic and clinical characteristics were abstracted. The data were analyzed by Chi-square and stepwise logistic regression. Forty-five percent of the patients were offered screening mammography within the study year and 53% were offered mammography over the preceding two years. Variables significantly associated with a request for screening included a previous history of breast disease (p < .001) and the severity of the patient's overall medical condition. Patients with an overall medical condition rated as mild were more likely to be requested to undergo screening than patients rated as moderately or severely ill (p < .01). Patients with higher educational levels were also more likely to be offered screening (P = .06). First year postgraduate (PGY 1) physicians requested more mammograms than PGY 2 or PGY 3 physicians (P < .05). A multivariable model utilizing logistic regression confirmed the association of the significant variables above with screening requests. Physicians were more likely to request mammography in patients at higher risk for developing breast cancer and less likely to request it in patients who had co-morbid illness. Increasing physician understanding of the importance and benefits of mammography and further investigation of strategies to ensure physician compliance with mammography recommendations are necessary to increase utilization.