Data drawn from semistructured interviews with 40 active street-level crack dealers are used to illustrate, apply, and expand the concept of restrictive deterrence. The article focuses on the perceptual shorthand dealers use to determine whether buyers in question are narcotics agents. In presenting this shorthand, the article seeks to demonstrate how interactions among marketplace democratization (i.e., the idea of selling to as many different customers as possible to maximize profits), marketplace volatility, transactional brevity, and threats from law enforcement affect its complexity and refinement. Respondents operated out of a medium-sized, midwestern metropolitan area within a central city of 390,000. Dealers' perceptual shorthand frequently includes three types of indicators: (1) deception clues grounded in appearance; (2) verbal clues grounded in unacceptable ways of asking for transactions, which involve incorrect references to the drug itself; and (3) various tests dealers use to either confirm or gainsay remaining doubts or suspicions about buyers' legitimacy. Footnotes, figure, references