This useful reference is a companion document to ATSSA's "Work Zone Positive Protection Toolbox." This guide describes the characteristics of work zones where positive protection is most appropriate; highlights specific, applicable aspects of Work Zone Rule Subpart K; and provides guidance on how to determine when to use different types of positive protection devices. The document is intended for use by planners, designers, and highway agency decision makers who develop their own individual policies/practices for implementation in the field.