In outlining the defense for entrapment, the author reviews the relevant U.S. Supreme Court decisions in Sorrells v. United States (1932), Sherman V. United States (1958), United States v. Russell (1973), and Hampton v. United States (1976). The primary criterion the Supreme Court used in deciding guilt or innocence in these four cases was whether or not the defendant was predisposed to commit crimes of the type charged (subjective test). The Court minority opinions argued for an objective test that would specify rules for police behavior. After reviewing arguments for and against these two types of tests for entrapment, the paper argues against the use of any police tactics to promote rather than detect crime. The author's guidelines for preventing entrapment include (1) permitting the use of techniques for observing law violations without violating citizen privacy; (2) prohibiting the use of friendship, sympathy, and inordinate gain to entice a person to commit crime; and (3) requiring judicial review to show probable cause that a targeted person is engaged in crime. A concluding section describes the implementation of procedures for preventing entrapment. Thirty-five notes are listed