Cognitive-behavioural family interventions for major mental disorder have undergone significant refinement over recent years. This paper reviews the current techniques for assessing mental disorder in the family. The initial task of the therapist is to undertake a comprehensive family assessment, including an assessment of their stress management. Specific information must be obtained about each family member's view of the presenting problems, interaction within the family system, and function in settings outside the family, as well as the family's effectiveness in problem solving and quality of life. Key goals of cognitive-behavioural family therapy are personal goal setting, education, and communication training that enhance the efficiency of family problem solving. The efficiency of cognitive-behavioural therapies in treating major mental disorders is also reviewed in relation to the family's ability to achieve specific goals in therapy and to modify the outcome of major mental illness. Particular attention is given to the strengths and weaknesses of the research, and to possible future research directions. Cognitive-behavioural family interventions are found to be effective in reducing clinical, social, and family morbidity.