In addition, a growing variety of centers (18-20%) are now run by healthcare facilities or physician groups, who utilize or employ their own clinic and administrative personnels or make use of existing company facilities to serve the worker population. Lastly, an increasing variety of employers are participating in shared, multi-employer centers, situated either on one employer's location or centrally situated.The vendor will develop, staff and manage the facility either at the request of a group of companies or will solicit companies in a defined geographic area. No matter the model used, it's essential that employer remain participated in provider choice, center oversight, strategic and policy direction. Staffing practices vary from one onsite clinic to another, though over 60% of centers are led by a Nurse Professional or Physician's Assistant.