This chapter reviews research and theoretical work pertaining to incest, describes the evolution of the most common types of incestuous family systems, and discusses some factors that may be helpful in assessing these families, including the issue of false accusations. The father in an incestuous family system may have been a victim of incest himself. Clinicians need to be wary about the concern for the family that often is professed by the father in an incestuous family system. The child in an incestuous family system is a truly tragic figure and a victim in every sense of the word. The victims of incest confuse some fundamental issues with regard to relationships. Many are unable to discriminate between erotic forms of contact and those which are simply affectionate or friendly. The process of determining whether a child’s allegation of incest is true or untrue should be undertaken with great care.