This chapter examines the potential benefits of computer-based adaptive instruction to human performance during the training of tasks usually conducted in extremely stressful work environments (e.g., law enforcement, firefighting, emergency medicine, or combat) that often include time, performance, and safety stressors. Adaptive instruction is training in which a computer-based intelligent tutoring system tailors its interaction with the learner to optimize learning and adapts the training environment (e.g., simulation) to maintain challenge level and flow. The design goal of adaptive instruction for tasks in extreme environments is to influence knowledge and skill acquisition to the point where the learner can successfully perform the expected tasks during training and then successfully transfer those skills to the work environment and perform regardless of the conditions. This chapter includes recommendations for representing and adapting work environment stressors during adaptive instruction to optimize learning and transfer of skills and is written for training developers.