More than one hundred OSHA standards for controlling workplace hazards contain requirements for worker training to reduce risk factors for injury and disease. Other standards limit certain jobs to workers considered competent by virtue of special training [Cohen and Colligan 1998]. However, the documented outcomes of various forms of training for occupational safety and health remain varied and inconclusive. Moreover, the newly proposed OSHA Occupational Safety and Health Program Rule [DOL 1998] redirects compliance audits to training outcomes and impacts (in the past, such audits focused on hours of training delivered). Given this change in approach, research will be needed to identify strategies for improving the measurable performance of mandated training programs. What's more, the economic reasons for expanded research are powerful. Each year, corporate America provides nearly 2 billion hours of training to approximately 60 million employees at a cost of $55 billion to $60 billion [Industry report 1997]. Training effectiveness research can maximize the impact of this investment on worker safety, productivity, and profits.