||Efficient use of commercial rabbit production facilities include housing the optimum number of rabbits per unit of area without adversely affecting the performance or the health of the animals. An experiment was conducted to determine the effect of pen design on animal production and management. Four different pen designs of equal area (0.74 sq. m) but of unequal perimeter were employed to ascertain the spacing relationships of domestic rabbits housed eight to a pen. Pen types were: 1) square pen, 2) square pen with four partitions (total length 1.7 m), 3) square pen with raised platform (0.10 m wide and 0.25 m high) attached to the interior walls of the pen, and 4) an equilateral triangular pen. Spatial and behavioral parameters were monitored one day each week for four weeks using time-lapse cameras. Weekly measurements of individual rabbit body weights were recorded. Individual head coordinates were digitized from the photographs. From the head coordinates, 3-dimensional surface plots were drawn of the sum of usage of each portion of each pen for the activity recorded weekly. The surface plots indicated there was variation among pen types and over weeks in spatial patterns. The locations most preferred by the rabbits could be determined from the 3-dimensional graphs. Distance to group center and distance to pen center were greatest for the platform pen, intermediate for the triangle pen and smallest for the partitioned and conventional pens. Female rabbits were heavier and rested more than male rabbits. The behavioral variables crouching and resting were highly correlated with initial weight, final weight and average daily gain. Rabbits that crouched more than they rested gained less weight. The percentage of time spent on the platform was 19, 23, 30 and 36 from weeks 1 through 4, respectively. The results suggest that the platform pen may be an effective means of reducing animal crowding by increasing the amount of space available to a group of animals.