Social judgment is a process of social explanation whereby one identifies which entities deserve credit or blame for multiagent activities. Such explanations are a key aspect of inference in a social environment and a model of this process can advance several design components of multi-agent systems. Social judgment underlies social planning, social learning, natural language pragmatics and computational model of emotion. Based on psychological attribution theory, this paper presents a computational approach to forming social judgment based on an agent’s causal knowledge and communicative interactions with other agents.