Purpose: The aim of this tutorial is to support speech-language pathologists' (SLPs') application of the International Classification of Functioning, Disability and Health (ICF) in assessment and treatment practices with children with language impairment. Method: This tutorial reviews the framework of the ICF, describes the implications of the ICF for SLPs, distinguishes between students' capacity to perform a skill in a structured context and the actual performance of that skill in naturalistic contexts, and provides a case study of an elementary school child to demonstrate how the principles of the ICF can guide assessment and intervention. Implications: The Scope of Practice and Preferred Practice documents for the American Speech-Language-Hearing Association identify the ICF as the framework for practice in speech-language pathology. This tutorial will facilitate clinicians' ability to identify personal and environmental factors that influence students' skill capacity and skill performance, assess students' capacity and performance, and develop impairment-based and socially based language goals linked to Common Core State Standards that build students' language capacity and their communicative performance in naturalistic contexts.