Foam plastic insulating sheathing (FPIS) has many applications within building envelopes that extend from the foundation to the roof. Its primary use has been to provide continuous insulation to achieve energy code compliance, as well as a means to minimize thermal bridging. However, FPIS can also play a role in many other building envelope objectives and functions. This presentation will introduce the American Chemistry Council’s Foam Sheathing Committee, explore the various applications of foam sheathing, and identify resources available to industry professionals. It will demonstrate the use of design tools such as wall calculators for coordinating energy code compliance for thermal performance and building code compliance for moisture control. Methods of attaching and supporting cladding and fenestration will also be addressed. Guidance regarding details for appropriate use of foam sheathing as water-resistive barriers, air barriers, and foundation frost-protection will also be featured.