Grice ("Syntax and semantics: Speech acts", 1975, pp. 41-58, Vol. 3) proposed that conversation is guided by a spirit of cooperation that involves adherence to several conversational maxims. Three types of maxims were explored in the current study: 1) Quality, to be truthful; 2) Relation, to say only what is relevant to a conversation; and 3) Quantity, to provide as much information as required. Three- to five-year-olds were tested to determine the age at which an awareness of these Gricean maxims emerges. Children requested the help of one of two puppets in finding a hidden sticker. One puppet always adhered to the maxim being tested, while the other always violated it. Consistently choosing the puppet that adhered to the maxim was considered indicative of an understanding of that maxim. The results indicate that children were initially only successful in the Relation condition. While in general, children performed better at first in the Quantity condition compared with the Quality condition, 3-year-olds never performed above chance in the Quantity condition. The findings of the present study indicate that preschool children are sensitive to the violation of the Relation, Quality, and Quantity maxims at least under some conditions.