The variables considered are security classification, age, race, marital status, type of offense, length of sentence, juvenile experience, prior adult sentences, census tract of residence, education at admission, and level of substance abuse. On April 1, 1982, the proportion of male inmates in open facilities was 28.9 percent; this figure was 28 percent on April 1, 1980, and 18.6 percent on September 1, 1977. During the past 5 years, there was a substantial increase in the number of inmates who were younger than 21 years but little change in racial composition of the inmate population. Three broad classifications of charges were considered: crimes against persons, crimes against property, and crimes neither against persons nor property. Breaking and entering or burglary was the most common offense among sentenced inmates on April 1, 1982, with this type of offender representing 23.2 percent of the sentenced population. Robbery was the second most common offense -- 22.5 percent of the population. For all 3 years, murder was the third most common type of offense. The median sentence lengths were high security, 12.2 years; maximum, 5.1 years; medium, 4.4 years; minimum, 2.9 years; and work release, 2.5 years. Extensive tabular data are provided.