While both psychopaths and sexual sadists engage in acts of predatory violence, little empirical work has examined the relationship between the two disorders. This paper outlines the constructs of psychopathy and sexual sadism and reviews the literature investigating the emotional lives of individuals with these disorders, paying particular attention to how emotional deficits might facilitate instrumental violence. Specifically, it is hypothesized that the emotion recognition and emotional experience deficits found among psychopaths, and perhaps present in sexual sadists, may lead to deficits in their ability to empathize with others, resulting in an increased likelihood for perpetrating instrumental violence. The relationship between empathy and aggression in psychopaths and sexual sadists is discussed, and distinctions are drawn between the two disorders with respect to their capacities to experience cognitive and affective empathy on a global level. Gaps in the literature are identified and additional areas of inquiry are suggested.