Abstract-Since there remains a need to examine the nature of the neural effect and therapeutic efficacy/effectiveness of sensory stimulation provided to persons in states of seriously impaired consciousness, a passive sensory stimulation intervention, referred to as the Familiar Auditory Sensory Training (FAST) protocol, was developed for examination in an ongoing, double-blind, randomized clinical trial (RCT). The FAST protocol is described in this article according to the preliminary framework, which is a synthesis of knowledge regarding principles of plasticity and capabilities of the human brain to automatically and covertly process sensory input. Feasibility issues considered during the development of the intervention are also described. To enable replication of this intervention, we describe procedures to create the intervention and lessons learned regarding the creation process. The potential effect of the intervention is illustrated using functional brain imaging of nondisabled subjects. This illustration also demonstrates the relevance of the rationale for designing the FAST protocol. To put the intervention within the context of the scientific development process, the article culminates with a description of the study design for the ongoing RCT examining the efficacy of the FAST protocol.