Vacuum deposited thin films are used for optical coatings, electrically-conductive coatings, semiconductor wafer fabrication, and a wide variety of other uses. They may be deposited on glass, plastic, semiconductors, and other materials. Usually, a vacuum deposition process produces durable, adherent films of good quality. But what do you do when things go wrong? Not all films can be deposited on all substrate materials. Sometimes films peel off or crack. Other times they are cloudy, absorbing, scattering, or have other unacceptable properties. This event will review techniques and tools that can be used to identify the source of the problems, correct the process, and get back into production. It will also help in learning how to develop new processes and products.