Patients with advanced cancer experience a complex web of problems, all of which interact. Specialist palliative care services have developed to meet these needs, but their effectiveness should be considered. We sought to determine whether specialist palliative care teams achieve their aims and improve outcomes for patients with advanced cancer and their caregivers, in terms of improving symptoms and quality of life and/or reducing the emotional concerns of family caregivers. We conducted a systematic review, searching standard databases augmented by reference lists of earlier reviews. The review focused on specialist (ie, with trained and dedicated professionals) palliative care in the home, hospital, or designated inpatient settings for patients with cancer. Outcomes were pain, symptoms, quality of life, use of hospital services, and anxiety. Studies were excluded if they did not test specialist palliative care services. We identified 8 randomized controlled trials and 32 observational or quasi-experimental studies. Overall, the evidence demonstrated that home, hospital, and inpatient specialist palliative care significantly improved patient outcomes in the domains of pain and symptom control, anxiety, and reduced hospital admissions. The results suggest that specialist palliative care should be part of care for cancer patients. Although the appraisal of evidence found improvements across domains, there is a need to understand better the effects of different models of palliative care and to use standardized outcome measurement.