This thesis attempts to determine if misconception about vapor retarders and air barrier systems affects building enclosure design and construction. Literature on this subject is continually evolving and often contradictory, supporting confusion. A survey of designers and builders representing four climate zones within the United States was done. Respondents disclosed where they learned about building enclosures and shared how clear or confusing they think the resources are on this subject and also weighed in on a few basic principles about enclosure design. Results show that most building professionals learn about enclosures through experience or a colleague. The internet is the first written resource they use when questions arise. The most significant misconceptions identified are that in some cases vapor retarder placement does not follow accepted building science or code requirements and that a portion of respondents only consider the air barrier system the vertical surfaces of an enclosure.