This position paper, written on behalf of the MASCC Psychosocial Study Group, reviews the most common psychosocial concerns and needs of cancer patients during all phases of the cancer continuum, from diagnosis to death or survivorship. Developments in psychosocial care at both individual and systems levels are surveyed and summarized, along with gaps in knowledge and research and needed improvements in the dissemination and application of acquired knowledge and expertise. The roles of culture, spirituality, and religion as part of psychosocial care are reviewed, along with families' and caregivers' specific psychosocial concerns and needs, and areas of needed psychosocial interventions in supportive cancer care. Deficits in recognizing and meeting patients' psychosocial needs at the system level are examined, and international guidelines and models of psychosocial care are reviewed, including their potential applications to local contexts. The paper calls for a shift to a new paradigm of care through adoption of an integrated approach to identify and meet the psychosocial needs of cancer patients and survivors as part of supportive care worldwide.