THE PURPOSE OF THIS CHAPTER IS TO PROVIDE A survey and overview of the results and findings of case studies of moisture problems in buildings. By case studies is meant any field study or pertinent and realistic laboratory study dealing with some aspect of actual moisture problems in buildings. Moisture modeling studies are not included, except occasionally where related to field or laboratory studies. The chapter describes research and studies published in the open literature as well as unpublished studies conducted by the author and others. An effort has been made to avoid hearsay, “conventional wisdom,” and other noncredible evidence with no factual basis. Most of the emphasis is on relevant U.S. and Canadian studies or experience.