Many learners with autism display inappropriate, maladaptive, and even aggressive behaviors towards others and themselves. Often, these behaviors stem from difficulties with communication, leading to unexpected and often undesirable methods to obtain certain wants, needs, and interests. Functional communication training addresses these interfering behaviors by systematically identifying the function of the behavior and providing a replacement behavior in the form of appropriate communication that will enable the learner to get his or her needs met in a more acceptable way. This evidence-based practice (EBP) overview on FCT includes the following packet components: (1) Overview; (2) Evidence-base; (3) Step-by-Step Guide; (4) Implementation Checklist; (5) Data Collection Sheets; (6) Tip Sheet for Professionals; (7) Parent Guide; (8) Additional Resources; (9) CEC Standards; and (10) Module References. [This brief was written by the Autism Focused Intervention Resources and Modules (AFIRM) team.]