Hospitalist systems create discontinuity of care. Enhanced communication between the hospitalist and primary care physician (PCP) could mitigate the harms of discontinuity. We conducted a mailed survey of 4,155 physician members of the California Academy of Family Physicians to determine their preferences for and satisfaction with communication with hospitalists. We received 1,030 completed surveys (26%). PCPs overwhelmingly stated that they "very much prefer" to communicate with hospitalists by telephone (77%), at admission (73%), and discharge (78%). Only discharge medications (94%) and discharge diagnosis (90%) were deemed "very important" by >90% of PCPs. Of the 556 respondents (54%) who had ever used a hospitalist, 56% were very or somewhat satisfied with communication with hospitalists, and 68% agreed that hospitalists are a good idea. Regarding communication at discharge, only 33% of PCPs reported that discharge summaries always or usually arrive before the patient is seen for follow-up. Only 56% of PCPs in our survey were satisfied with communication with hospitalists. Hospitalists should communicate with PCPs in a timely manner by telephone, at least at admission and discharge, and provide the specific pieces of information deemed important by the vast majority of PCPs. Hospitalists should also ensure that discharge information arrives in time to assist the PCP in reassuming care of their patients. It may be possible to tailor communication to individual PCPs. Further research could assess the impact of such communication on patient satisfaction and outcomes.