Current psychiatric classification systems, including the DSM, do not fully reflect the complexity, heterogeneity, and dimensional nature of mental disorders or adequately incorporate biological, developmental, contextual, and functional factors into clinical decisions. A more scientifically grounded, patient-centered framework is needed to integrate emerging evidence across multiple levels of analysis and support increasingly specific diagnoses as evidence develops. This lecture will present a proposed modular diagnostic approach and practical tools for incorporating biomarkers and biological factors, transdiagnostic symptoms, contextual factors such as social and environmental determinants of health, developmental and life-course factors, functioning, quality of life, and medical comorbidities into diagnostic formulation. Learners will gain a framework for making more comprehensive, dimensional, individualized, and recovery-oriented diagnostic assessments.