The incorporation of deuterium into drug candidates has evolved from a specialized isotope-labeling technique into a strategic medicinal chemistry approach used to address key development challenges, including those encountered in CNS therapeutics. Over the past decade, several deuterated compounds have advanced into clinical development and commercialization, demonstrating the potential to modulate metabolic pathways while maintaining the desired pharmacological profile of a molecule. This poster reviews the scientific principles underlying deuteration, highlights examples from approved and clinical-stage CNS programs, and discusses practical considerations in the design, synthesis, and development of deuterated compounds. Particular emphasis will be placed on synthetic strategies, isotope incorporation approaches, scale-up considerations, and the chemistry challenges associated with advancing deuterated candidates from discovery through development.