We describe a generic approach for modeling the impact of emotion on cognition, perception, and behavior. The approach can model the effects of transient emotional states, longer moods, and stable personality and temperamental factors. The underlying assumption is that one of the primary ways in which emotions influence cognition and perception is by modulating a variety of processing parameters. We illustrate the approach in the context of both a generic integrated architecture of cognition, and a specific architecture, currently under development, designed to model decision making behavior. In this context, we illustrate how the approach would be instantiated within several representational formalisms (e.g., rules, belief nets). We focus on modeling the impact on tactical decision-making of three specific emotional states that have been studied extensively in experimental psychology: anxiety, negative affect (e.g., depression), and obsessiveness. The proposed approach can then be used both for investigating the interaction between cognition and emotion, and the resulting behavior, and for modeling specific types of personalities in interactive environments.