BACKGROUND Nutrient and caloric intake is critical during therapy for head and neck cancer. METHODS The authors review the oral complications experienced by, and dietary and nutritional needs of, patients during therapy. They also present recommendations for oral care and calorie and nutrient intake. CONCLUSIONS Oral health care professionals can assist patients during treatment for cancer in maintaining oral, systemic and nutritional health, as well as in controlling oral symptoms. Recovery from the acute toxicities of therapy often requires diet modification, tube feeding or both to meet patients' energy and nutrient demands. CONCLUSIONS Effective management of oral complications of therapy for cancer is necessary to facilitate oral intake throughout treatment. Oral health care professionals should be part of the multidisciplinary team helping meet the needs of patients during treatment.