The article reviews the effects of music and music therapy with adult oncology patients, summarizes major findings, discusses the difficulties inherent in research methodologies, and explores directions for future research. Although there is more qualitative than quantitative research, empiric investigations have found that music techniques are effective in managing pain and other physical symptoms, psychological distress, and mood. Health-related outcomes and quality of life have also been improved. Recommendations for future research include collaborative projects that (1) test established music therapy clinical protocols; (2) control for the presence of a music therapist; (3) identify the characteristics of patients who will potentially benefit most; (4) examine physiologic, psychological, behavioral, neurologic, immunologic, and spiritual outcomes; and (5) detect and control extraneous variability.