This study investigated alternative instructional delivery modes in two different short courses for professional engineers and scientists. Two math-oriented courses were taught to 130 participants. Each course was taught twice, once using the blackboard exclusively and once using extensive view graph projections (20 to 40 transparencies per 90-minute lecture). Each course was offered once on the east coast and once on the west coast. Participants were given pretests of cognitive background and demographic identification. Cognitive and affective posttests were given at the end of a 5-day course and at five weeks and four months following the course. Results of the study with four test classes revealed that blackboard and view graph presentation modes did not produce statistically significant differences in achievement of learning objectives in mathematics-oriented short courses. Student satisfaction was also similar for the two teaching modes. (Author/CS)