Inmates of a Federal corrections institution provided urine samples assayed for epinephrine and norepinephrine, and they supplied self-report data on their perceptions of crowding. A review of infirmary records yielded inmates' health histories. Inmates resided in one of three housing types that varied by the degree of privacy and crowding afforded. Private cells provided the lowest social density, and open dormitories had the highest. Partitioned dormitories or cubicles provided intermediate social density. Across all inmates, perceived crowding was positively correlated with levels of urinary catecholamines. Single-cell inmates reported less crowding and exhibited lower levels of urinary catecholamines than dormitory inmates; however, there was not a good linear relationship between increasing social density and increasing levels of each of the dependent measures. Cubicle inmates had the highest level of illness complaints, but their catecholamine levels were comparable to those of single-cell inmates. Findings are consistent with other studies in showing that cubicles provide positive reactions on some dimensions but not on others. 6 tables, 33 references. (Author abstract modified)