OBJECTIVES We explored oncologists' attitudes toward the costs and cost effectiveness of cancer drugs and their views on various reimbursement policies in the United States. METHODS We surveyed 1379 oncologists based in the United States, selected from the American Society of Clinical Oncology (ASCO) membership list. Self-administered surveys were disseminated by mail between January and August 2008. The survey covered the degree to which oncologists believe that treatment costs and patients' out-of-pocket spending influence their prescribing behavior. We also asked whether the oncologists discuss costs with patients and about the potential use of comparative effectiveness and cost effectiveness information. RESULTS A total of 787 oncologists responded (response rate 57%). Sixty-seven percent of respondents stated that every U.S. patient should have access to effective cancer treatment regardless of cost; however, 56% stated that costs influenced their decisions about which cancer treatments to recommend, and 84% agreed that patient out-of-pocket costs influenced decisions. Only 42% said they always or frequently discussed cost issues with patients. A majority (80%) supported more use of cost effectiveness data in coverage and payment decisions; only 41% felt well prepared to interpret and use such information. Respondents leaned toward more government intervention: 57% agreed that government price controls for cancer drugs for Medicare were needed; 79% favored more government research on the comparative effectiveness of cancer drugs. After adjusting for other factors, older MDs were more likely to be influenced by cost and more likely to discuss costs with patients. CONCLUSIONS Oncologists believe that costs influence their prescribing, yet relatively few report discussing costs frequently with patients. The results highlight the need to educate physicians about treatment costs and cost effectiveness and to develop better communication strategies. They also support research on the comparative effectiveness and cost-effectiveness of cancer therapies.