This paper presents a method to estimate induced abortion rates in different countries based mainly on regression equations featuring contraceptive prevalence and total fertility. For the more developed countries with presumably reliable abortion reporting, the first equation shows an extremely close fit. The principal predictor is the proportion of married women using modern methods of contraception. For less developed countries, other equations depend mainly on both modern method use and total fertility and are more questionable since reliable external estimates of abortion are less available. Estimates of abortion rates are nevertheless presented for a large number of less developed countries, based on recent data on contraceptive prevalence and fertility from a variety of sources.