Book excerpt: Presents an overview of quantitative measurements in forensic science Outlines a foundation of basic mathematical and statistical concepts using applied examples from forensic science Provides practitioners the tools required both to develop uncertainty estimations and to evaluate and improve existing ones Describes how to build uncertainty budgets and worksheets Suggests top-level practices and procedures for seized drug analysis, toxicology, breath and blood alcohol, and distance/length measurements Offers a wealth of free, and easily accessible, supplementary references and Web resource