OBJECTIVE: To review investigation and management of some common long-term complications associated with cancer chemotherapy and radiation therapy. QUALITY OF EVIDENCE: Databases searched using MeSH key words "cancer chemotherapy," "cancer chemotherapy complications," "radiation therapy," and "radiation therapy complications" included Ovid and CANCERLIT. Overall the literature in this area is not strong; treatment guidelines and consensus conferences generally are lacking. Recommendations in this paper are mainly based on the results of individual studies and case reports, as few randomized controlled trials have been performed. Where appropriate, recommendations incorporate results of published treatment guidelines and consensus conferences. MAIN MESSAGE: For most solid tumours, patients should be most frequently monitored during the first 3 years after completing initial treatment for cure. Follow-up monitoring usually incorporates physical examination as well as radiologic and laboratory investigations. Patients should not be lost to follow up once treatment is completed, but monitored regularly, especially while they are at highest risk for disease recurrence. Long-term complications associated with cancer therapy include postsplenectomy sepsis syndrome; central and peripheral nervous system toxicities; ocular complications; thyroid, pituitary, testicular, or ovarian dysfunction; pulmonary toxicity; vascular or lymphatic, gastrointestinal, or osseous complications; genitourinary problems; and possible secondary malignancy. CONCLUSION: Primary care physicians are key to facilitating appropriate follow up of treated cancer patients. To do this, they must be aware of practical aspects of monitoring and management of therapy-related complications.