Abstract Purpose Shared Decision-Making (SDM) enhances patients’ satisfaction with a decision, which in turn increases compliance with and adherence to cancer treatment. SDM requires a good patient-clinician relationship and communication, patients need information matching their individual needs, and clinicians need support on how to best involve the individual patient in the decision-making process. This survey assessed oncological patients’ information needs and satisfaction, their preferred information in patient decision aids (PDAs), and their preferred way of making decisions regarding their treatment. Methods Questionnaires were distributed among attendees of a lecture program on complementary and alternative medicine in oncology of which 220 oncological patients participated. Results Participants reported a generally high need for information—correlating with level of education—but also felt overwhelmed by the amount. The latter proved particularly important during consultation. Use of PDAs increased satisfaction with given information but occurred in less than a third of the cases. Most requested contents for PDAs were pros and cons of treatment options and lists of questions to ask. The vast majority of patients preferred SDM to deciding alone. None wanted their physician to decide for them. Conclusions There is a high demand for SDM but a lack of conclusive evidence on the specific information needs of different types of patients. Conversation between patients and clinicians needs encouragement and support. PDAs are designed for this purpose and have the potential to increase patient satisfaction. Their scarce use in consultations calls for easier access to and better information on PDAs for clinicians.