Selected invasive diagnostic and therapeutic techniques were taught to emergency physicians through modular Advanced Trauma Life Support (ATLS) animal laboratory courses presented in the fall of 1977. Thirty-seven emergency physicians participated in the four pilot ATLS laboratories in which the average trainee:animal:instructor ratio was 2:1:0.75. The animals consisted of 15 large baboons and five large rhesus monkeys. Cost accounting on these pilot ATLS courses revealed that the total program cost was $15,581.86, for an average of $3,895.46 per trauma laboratory course and $421.13 per emergency physician trained. The ATLS concept is ready for development into a nationally-standarized ATLS series.