Introduction to Substance Use and Misuse (2026) is an open educational resource that examines substance use, misuse, and recovery through the lens of social work while drawing upon the contributions of multiple health and human service disciplines. Recognizing that substance use disorders frequently occur alongside mental health conditions and are influenced by trauma, family systems, culture, and the broader social and political environment, the text explores the complex interactions that shape care across the continuum. It emphasizes a person-centered, recovery-oriented approach to interprofessional collaboration across prevention, assessment, treatment, and recovery. Throughout, theory is connected to practice through critical reflection, evidence-informed decision making, and authentic application, preparing future professionals to work ethically and effectively with individuals, families, groups, and communities. Developed for the SW 4050/5050 Introduction to Substance Use and Misuse course at Middle Tennessee State University, the text is designed to support both undergraduate and graduate learners.