Smart drug delivery systems represent a paradigm shift in pharmaceutical sciences, integrating advanced nanotechnology, personalized medicine approaches, and theranostic capabilities to achieve enhanced therapeutic outcomes with reduced side effects. This comprehensive review examines the current state and future prospects of intelligent drug delivery platforms that utilize responsive mechanisms, targeted delivery, and real-time monitoring capabilities. The global smart drug delivery systems market, valued at $12 billion in 2024, is projected to reach $48.3 billion by 2034, reflecting a compound annual growth rate of 17%. This growth is driven by the increasing prevalence of chronic diseases, which account for 74% of global deaths according to the World Health Organization, and the urgent need for more effective, personalized therapeutic interventions. The integration of nanotechnology platforms, including liposomes, polymeric nanoparticles, and protein-drug conjugates, with biomarker-guided targeting and theranostic imaging capabilities, offers unprecedented opportunities for precision medicine. Recent FDA approvals of 18 personalized medicines in 2024, representing 38% of all newly approved therapeutic entities, underscore the regulatory acceptance and clinical potential of these advanced delivery systems. This article provides a comprehensive analysis of current technologies, clinical applications, regulatory landscape, and future directions in smart drug delivery systems.