This case concerns allegations by the Texas Medical Association, the Texas AFL-CIO, Patient Advocates of Texas, and Doctors Allen J. Meril and L.E. Richey (collectively, the appellants), that the 2002 medical fee guidelines promulgated by the Texas Workers Compensation Commission are invalid. See28 Tex. Admin. Code ‘134.202 (2003). Appellants assert substantive and procedural challenges to the Commission=s rule establishing the 2002 fee guidelines. For the reasons that follow, we affirm the judgment of the district court declaring the 2002 fee guidelines valid and denying a permanent injunction to restrain the guidelines=implementation.