This paper presents data bearing on the question of the effects of crowding on indices of stress and on one's perception of being crowded. A palmar sweat measure of stress was employed to examine inmate stress in relation to social and spacial density factors. The data suggest that increasing the number of people in a housing unit (and hence the potential number of interactions) leads to increases in levels of stress as measured by palmar sweat. In contrast, decreasing the amount of space per man does not lead to such increases in levels of stress. Apparently the social component of crowding appears to be the more important variable in producing crowding stress. The authors also employed a figure placement task developed by Desor to assess the degree to which the inmates tolerate stress. The figure placement data suggest that individuals living under relatively high levels of social density develop greater tolerance for crowding than those living under lower levels of social density. This finding is in agreement with an adaptation level theory analysis of responsitivity to stress. (SJL)