Drug development is highly regulated to ensure patient safety for marketed drugs and new chemical entities (NCEs) in development. While current guidelines on quality such as those published by the International Conference on Harmonization (ICH) are more detailed and prescriptive regarding requirements for commercial drug substances and drug products, much less guidance is available specific to NCEs during clinical development. Analytical chemists must strategically develop test methods and control strategies in parallel with and to guide process chemists while developing, optimizing, and scaling up drug substance manufacturing and to guide formulation scientists developing drug product dosage forms. These analytical procedures are necessary to ensure the identity, strength, quality, purity, and potency of each drug substance and drug product manufactured for human use. This presentation will provide analytical strategies to support CMC drug development from preclinical phase to commercial production, with a focus on drug substance programs.