Purpose: To explore the sociodemographic and clinical characteristics of cancer patients seeking a second-opinion consultation and to analyze their second opinion-related motives, needs, and expectations.Patients and Methods: In 212 consecutive patients seeking a second opinion at the Surgical Oncology Outpatient Clinic, satisfaction with the first specialist, motivation for the second opinion, need for information, preference for decision participation, and hope for and expectation of a different second opinion were assessed with a questionnaire.Results: The mean age was 53 years. Most patients were women (82%), of whom 76% were diagnosed with breast cancer. Half of the patients (51%) had a low educational level. The majority of patients (62%) only had internal motives for second-opinion seeking associated with the need for reassurance and more certainty, whereas a substantial minority of patients (38%) also had external motives related to negative experiences or unfulfilled needs. The externally motivated patients had a higher anxiety disposition, were less satisfied with their first specialist, preferred a more active role in medical decision making, and more often hoped for and expected a different second opinion.Conclusion: Motives for second-opinion consultations differ greatly. Understanding the difference between internal and external motivation is necessary to develop strategies to prevent unnecessary second-opinion seeking. Additional studies are warranted to evaluate the objective and subjective outcomes of second-opinion consultations.