Part of a larger project designed to produce a causal model of variables that impinge upon training interventions and influence adult learning, this research is concerned with learner attitudes toward the way employee training is delivered and the roles these convictions play in learning. Two research models served as a guide for comprehensive data collection in four studies of major plant safety training programs. The first three studies were concerned with energy control and power lockout (ECPL), safety training for operators of powered material handing vehicles (PMHV), and plant pedestrian safety. Instruction was delivered via group-oriented lectures and discussion with supporting videotapes in all three programs. The fourth study related to the same ECPL content as the first study, but the training format had been converted to interactive videodisc instruction. The studies employed a pre-/posttest survey design with the posttests administered 30-90 days after training. Two trainee populations for each study, hourly and salaried personnel, came from randomly selected classes in five to seven plants. Results of the studies showed that the subjects consistently preferred instructor-delivered delivery, and that self-directed learning methodologies were generally the least desirable for all groups. It was also found that adult attitudes toward training and the ways in which training programs are conducted do influence the fundamental success or failure of these programs both in the amount learned and in the generalized transfer of training principles to the workplace. A model of those factors which contribute to these training outcomes has been constructed and described. Two appendices provide additional information on the measurement of variables and path diagrams supporting a general model of delivery system preference effects. (14 references) (BBM)