In this first installment, we’ll identify and briefly discuss a few of the reasons why many HVAC systems either fail outright or give less than satisfactory performance. The reasons may be technical, contractual or even simply a matter of perception. The failure may be relatively minor or catastrophic. Whatever the root cause of a real or perceived system failure, the matter may wind up in litigation or other situation that strains the relationship between the owner and the design/build team. Understanding the root causes may lead to better projects or at least better relationships between the parties that can help to avoid or minimize the damage caused by disputes. While the issues addressed will be discussed from the perspective of HVAC systems, many of the reasons and the potential solutions, can be applied to other building construction systems — lessons learned here may have more universal application than first appears.