P's and Q's is a phrase that means to be cautious and mindful of one's behavior and manners. It originated from the 17th-century English pubs where bartenders would keep a tally of how many pints and quarts of beer a patron consumed. If the patron became too drunk and disorderly, the bartender would remind them to "mind their p's and q's." Some synonyms for this phrase are "be on one's best behavior," "mind one's manners," "show good etiquette," "mind one's language," and "act appropriately." These phrases all suggest that it is important to be aware of one's behavior and to communicate respectfully and courteously with others.
