Like other dangerous but pleasurable activities, such as downhill skiing and mountain climbing, engaging in unprotected sex implicitly involves the weighing of costs and benefits. Recognizing that the transmission of the AIDS virus is a consequence of private choices - rational and often informed - to engage in risky conduct, the authors employ tools of economic analysis to reassess the orthodox approach to AIDS by the public health community. Standard predictions of the spread of AIDS, the authors argue, are questionable because they ignore rational behavioural response to the risk of infection. For the same reason, customary recommended public health measures, such as exstensive testing the AIDS virus, not only may be ineffective in controlling the spread of the disease but may actually cause it to spread more rapidly. The authors examine regulatory measures and proposals such as mandatory esting, criminal punishments, and immigration controls, as well as the subsidization of AIDS education and medical research, the social and fiscal costs of AIDS, the political economy of the government's response, and the interelation of AIDS and fertility risk. Neither liberal nor conservative, the tone of the book is, on the whole skeptical about governmental involvement in the epidemic.