This study aimed to describe the attitudes of patients with breast cancer and those with prostate cancer toward complementary therapies. The data were collected with a postal questionnaire administered to 216 patients with breast cancer (response rate, 55.4%) and 1 90 patients with prostate cancer (response rate, 54.9%) in southern and southwestern Finland. The questionnaire was composed of 44 Likert-type statements, which were analyzed using descriptive statistics, chi2 tests, t tests, and two-way analyses of variance. More than half (54%) of the patients with breast cancer and 45% of the patients with prostate cancer believed that people with cancer may benefit from complementary therapies, although they did not think these therapies actually could cure cancer. More than half of the respondents were dubious about using complementary therapies as long as there was no solid scientific evidence. Most believed that complementary therapies were used because they gave people hope (women, 88%; men, 72%) or "something to cling to" (women, 83%; men, 76%). The respondents believed most in dietary therapies and least in healing. There was much confusion and uncertainty about the professional competencies and expertise of the people who provided complementary therapies. Approximately one fourth of the respondents had spoken to their physician about complementary therapies. Only a few had talked about the matter with nursing staff. About half of the respondents thought that physicians and nurses took a negative attitude toward complementary therapies. In both groups, patients who had talked with their physician about complementary therapies tended to show a more positive attitude.