This study examines preschoolers' acquisition of the maxims of the Cooperative Principle and the sociocognitive scaffolds that support this acquisition. In Study 1, 84 children between 3 and 5 years old were required to make passive judgments of violations of the Cooperative Principle. Results showed that children consistently identified violations of the Cooperative Principle and their performance improved with age. In Study 2, a subgroup of 38 children between 3 and 4 years old completed a standard false belief (Theory of Mind) task. Both groups identified violations of the Cooperative Principle at a level better than chance, although neither age group passed the false belief task at a level better than chance. This study joins previous research in placing the emergence of the Cooperative Principle in the preschool years. Results also suggest that false belief understanding is not a prerequisite for recognizing violated maxims of the Cooperative Principle in routine conversational exchanges.