A computer program was written to simulate ground vibrations induced by multiple-hole surface blasts. The program is an inexpensive and relatively easy to use tool for predicting the principal blast vibration characteristics that determine damage and annoyance potential: peak particle velocity, frequency content, and pulse duration. The program generates a complete ground motion history by superposing at any surface position the vibrations induced by each individual explosives charge. It requires specification of and allows accounting for the blast geometry, initiation sequence, position with respect to blast, pulse characteristics induced by each charge, and propagation laws. The main difficulties are backcalculating individual pulses, propagation, parameters, and delays. Normal distribution of delays influences the results and the response of a single degree of freedom structure significantly.