A book about parenting which separates the facts from personal opinion and professional theory. The Fishers, both psychologists, have read through the research and summarized the relevant data on security, discipline, sex, school, adolescence, single-parent homes. Much of it, as they readily admit, is common sense and fairly standard middle-class practice. They are careful to distinguish those techniques and attitudes which are supported by research (weaning after six months or more) from those that are considered harmful (regular physical punishment) and from those with inconclusive results (how to talk about sexuality) or which have not been studied at all. The last is the largest category and as clinicians they make their own suggestions, following the guidelines of these findings and their own professional experience. The general policy: avoid extremes; maintain good communication; provide friendliness and warmth; be consistent and flexible. What We Really Know then is not new; although it is authoritative on the research that has been done, many of the most important problems parents face have not been studied so its use for particular situations is limited. A thorough job, though, and a help in evaluating all the other books about bringing up baby.