Increasing numbers of PV systems of all types are being installed throughout the United States due to widespread financial incentives and a heightened awareness of energy issues. Using the mature PV module technology and proven balance-of-systems (BOS) equipment, well-trained and experienced PV designers and installers following the best available information and codes are providing PV electrical power systems that are safe, durable, reliable, and well performing. About 50% of the surveyed installations met this goal. However, the remaining 50% of the installed systems had deficiencies in these same areas of safety, reliability, durability, and performance. Examples of both systems are presented and suggestions for improvements are offered.