A description is given of an automatic method for producing numerical and graphical statements about movement and inter-organism or organism-environment interaction patterns from observational records. The method is based on use of Cartesian co-ordinates to represent the position of each individual at each instant sampled. In addition to statistical computations regarding distances travelled, the frequency of entry into specified territories, sociometric and other parameters, movement maps can be produced with the aid of a plotting device connected to a computer. The program can be adapted for various investigations concerning social interaction, territoriality, equipment usage, activity habits, and architectural design. © 1969.