The author reviews recent sociobiological and psychoanalytic literature relevant to sexual aspects of the male Oedipus complex. Sociobiological discussions of incest and incest avoidance frequently contrast Freud's Oedipus complex with the Westermarck hypothesis. Westermarck argued that children who grow up in close association are averse to sex with each other as adults. Human and animal evidence supports the Westermarck hypothesis, and sociobiologically oriented writers have argued that it contradicts Freud's oedipal notion of an early incestuous sexual interest. However, two additional lines of evidence are relevant to such discussions. First, recent analytic theory on the Oedipus complex does not require the existence of a central, powerful, incestuous sexual drive. Second, both oedipal and sociobiological theory suggest that early familial experience forms a model for adult sexual mate choice and establishes patterns of adult sexual relationships. In these instances, sociobiological understandings of early development correspond well to oedipal theory.