Systemic psychotherapists work therapeutically with individuals, couples and families, and offer consultation and systemic interventions with teams, agencies and organizations. The overwhelming findings from the research reviews and meta-analytic studies is that family therapy works compared to untreated control groups, with some demonstrated superiority to standard and individual treatments for certain disorders and populations. This chapter provides a list of people and problems who have found to benefit both clinically and significantly from the couples and family systemic psychotherapies compared to no psychotherapy; the list includes marital/couple distress and conflict, and outpatient depressed women in distressed marriages. Family therapy seems to be more cost-effective than standard inpatient/residential treatment for schizophrenia and severe adolescent conduct disorders and delinquency. Visits by family members to primary healthcare practitioners were reduced following family therapy intervention. The chapter ends with a discussion on the methodological problems and innovations which set the challenge for the future.