As of January 1, 1984, 85 jail-type facilities were being operated by county or county and municipal units of government and were classified as adult corrections, adult detention, jail, lockup, holding, work release, condemned, or contract limitation facilities. Analysis reveals that the average daily populations and the ratio of persons confined in these facilities increased significantly between January 1, 1975, and December 31,1983. Only 49 counties appear to have facilities of the type and size needed to meet their needs to the year 2000. Counties faced with the possibility of large capital expenditures to meet increased jail capacity needs should consider alternatives to detention. Fourteen tables delineating prison population and capacity are included.