Whether a nurse practitioner (NP) is employed by a medical practice or Is self-employed, the reimbursement pollcles of third-party payers will determine whether an NP continues to provide care on a long-term basis. The payers-Medicare, Medicaid, indemnity insurers, and managed care organizations-each have their own reimbursement policies and fee schedules, and each operates under a separate body of law. Some payers have a history of reimbursing for NP services in the same manner as they reimburse for physician services. On the other hand, some payers have recently begun to relrnburse NPs directly, either as separate and apart from an employment relationship with a physician practice or following NP-specific rules and policies regarding reimbursement. This article offers basic information necessary to communicate with practice managers, billing experts, and the payers about reimbursement mechanisms and problems. It covers how to set up provider relationships with the various payers, how to submit bills, and how to deal with denial of reimbursement when it occurs.