The Comprehensive Behavioral (ComB) conceptual model is introduced in this chapter. Here, three phases of BFRB behaviors: Preparatory behaviors, pulling or picking behaviors, and post-removal behaviors are detailed. The functional assessment of individual BFRB practices is emphasized, in which antecedent variables, both internal and external to the individual are described, as are possible consequences of pulling, both of which impact on the performance and perpetuation of BFRB activity. Identification and description of antecedent and consequential variables (sensory, cognitive, affective, and motor) emphasize the complexity and heterogeneity of internally experienced BFRB experiences that impact on BFRB persistence. The ComB conceptual framework described here sets the stage for ComB-based clinical interventions introduced in later chapters.