An independent, certified commissioning authority, under contract to the owner is the preferred contractual arrangement because a third party professional brings objectivity and practical experience to the project to ensure that the owner will truly get the building performance that he or she expects. ACG members must be independent.

Although contractors may have the knowledge and capability to test the equipment they install, they may not be skilled at testing or diagnosing integration problems. In addition, some contend that it is difficult for contractors to objectively test and assess their own work, especially since repairing deficiencies found through commissioning may increase their costs.

It is important to involve the independent commissioning authority as early in the project as possible. This allows the provider the opportunity to review the design intent for the project, begin scheduling commissioning activities, and begin writing specifications into bid documents for other contractors.