Profound changes in sexual attitudes and practices throughout society are raising serious questions about the adequacy of traditional Catholic formulations for a responsible sexual life. This thorough, balanced and insightful scholarly study is a document that will almost certainly shape discussion of sexuality for years to come. In the biblical study a special effort has been made to separate the revealed and lasting message from what is culturally conditioned and subject to change. The approach to tradition is similar, solidly historical, distinguishing constant values from changing historical and cultural influences that have up to now coloured Catholic attitudes. Data from a wide range of empirical scientists and experts are summarized and evaluated. Then the worlds of scripture, history and anthropology are brought together in a theological synthesis from which the authors elaborate principles for interpreting and evaluating sexual activity. A final section faces directly the major sexual questions of today in the light of the principles this study develops.