PURPOSE OF REVIEW: Effective communication in cancer care requires complex communication skills of healthcare professionals (HCPs), which can be advanced by communication skills training (CST). The number of empirical studies on CST has grown steadily over the last decade. However, controversies on CST abound. The aim of this review of reviews is to summarize evidence for the effectiveness of CST in oncology as well as for effective CST features (intensity, format and content) and to synthesize the current opinion on CST. RECENT FINDINGS: The evidence synthesized from multiple reviews supported the effect of CST on HCPs' communication skills. Yet, the certainty of evidence was limited as studies were diverse and effects heterogeneous. Furthermore, limited evidence was found for effective CST intensity, format and content. Authors of the reviews advocated further high-quality research with robust outcome measurement to establish the most essential features of CST and recommended implementation of CST in the standard training of HCPs with continuous supervision. SUMMARY: CST can probably improve some aspects of HCPs' communication skills. Despite the uncertain evidence, implementation of CST into clinical practice is widely advocated and specific recommendations regarding intensity and format are provided. Evidence to justify and substantiate implementation efforts is needed.