This chapter presents a series of closely connected theories, principles, and conceptual frameworks that provide several practical implications for the construction of organizational simulations. A basic theory of psychology is that behavior is a function of both the person and environment, in interaction. The number of potential situational characteristics is even larger than the number of personal characteristics. Two taxonomies of situations provide frameworks from which designers of simulations can draw. The simulation presented high fidelity in the content of the calls, time demands of the job, and actions of entering customer information and activating a button, much like the job. Theories of psychology, observation, judgment, and measurement provide valuable insights into the processes of constructing and implementing simulations. Simulations used for training/development might include several elements, such as letting participants try multiple solutions to a problem; providing feedback at multiple points; and focusing on the ability to learn from mistakes and do better in subsequent trials.