Sections 1961-1968 of Title 18, U.S. Code, or RICO, were enacted as Title IX of the Organized Crime Control Act of 1970. Prior to RICO, illicit economic activities which generated profits for criminal organizations were outside the scope of criminal law, and prosecutors had to confine their cases to proving fraud, extortion, or fencing stolen goods. RICO outlaws specific activities partly by using existing Federal and State laws, but adds the concept of enterprise to a criminal prosecution. Enterprise is defined as an individual, partnership, corporation, association, or other legal entity and any union or group of individuals associated in fact although not a legal entity. The statute proscribes the following types of relationships between the criminal and an enterprise: legal acquisition with illegal funds, illegal acquisition through illegal means, illegal use of enterprise, and conspiracy. These criminal provisions are summarized and illustrated with cases. The portions of Section 1961 which define enterprise are examined in detail as they relate to businesses, labor unions, government agencies, and groups of individuals associated in fact. Guidelines are provided for establishing violations under Section 1962, conspiracy, by proving a pattern of racketeering activity or collection of an unlawful debt. Procedures are outlined for implementing the criminal forfeiture provision, Section 1963, which mandates forfeiture to the United States of any interest acquired, operated, or conducted in violation of Section 1962. Civil remedies established by Section 1964 for the Government and private parties are also covered, including divestiture and dissolution, collateral estoppel, and venue and process. Because RICO permits the court and jury to see for the first time criminal activity from the financial vantage point of the criminals, it is a unique change in the law enforcement system.