The process of preparing and reviewing a contract for a pharmacy computer system is described. The purpose of the contract is to establish rules governing the relationship between the vendor and the buyer. It should identify clearly the performance expectations of both parties. The contract negotiating process also allows each party to gain insight to the other's motives by way of responses to proposals for specific contract inclusions. Generally, the buyer should be wary of: (1) a vendor who insists that his form contract be signed without modification; (2) signing more than one contract with the same vendor; (3) vague, nonquantifiable performance criteria; (4) "best-efforts" warrantees; (5) an expectation that difficulties with the vendor can be solved if the remedy is not in the contract; and (6) acceptance upon delivery. The buyer should strive for: (1) a complete contract reflecting the nature of the business deal negotiated, (2) specific performance criteria, (3) warrantees of performance with meaningful remedies, and (4) payments tied to performance. The most important provision of the contract is the one that makes payment to the vendor contingent upon the actual demonstration of results.