Functional Behavioral Assessment is a comprehensive technical manual, written for animal behavior technologists. It explains why the functional behavioral assessment approach is the most effective and efficient means of assessing problem behaviors in non-human animals and provides a detailed description of how to conduct the functional behavioral assessment. Functional assessment interviewing, direct observation, quantitative tracking, and functional analysis procedures are elaborated. A functional Assessment Interview form is provided for the reader's use. Also provided for the reader is a differential functional diagnostic flowchart. An introduction is provided on deriving a formal behavior change plan from the functional assessment products. The emphasis is placed on working with dogs in terms of examples but the approach is easily adapted to working with parrots, cats, horses and other species, including humans.