The commissioning engineer's role continues to grow as building owners continue to look for more and more technical support due to apparent concerns owners have with the design and building process. It is not that the commissioning engineer (CxE) is the "last answer" in engineering and construction as much as a source for providing another opinion. Perception can be reality for most, so the perceived lack of confidence the owner may have in the designer or the builder or both can lead to more involvement by the CxE. Unfortunately, this expanding project role can create conflicts between the engineer-of-record and the CxE. It also can complicate the CxE's working relationship with the general contractor or construction manager.