This book presents a detailed examination of the transformative impact of three-dimensional (3D) printing on the development of transdermal microneedles for drug delivery. It offers a comprehensive overview of recent technological advancements, encompassing novel materials, emerging fabrication strategies, clinical translation, and evolving regulatory frameworks. The opening chapter introduces the fundamental concepts of 3D printing as applied to microneedle devices. The book then explores a wide range of additive manufacturing techniques used in microneedle fabrication (e.g., stereolithography, selective laser sintering), followed by in-depth coverage of state-of-the-art 3D printing methodologies-including stereolithography, digital light processing, and other photopolymerization-based technologies-as well as advanced biomaterials such as stimuli-responsive polymers and specialized bio inks. Readers will gain insight into the integration of artificial intelligence in microneedle design, innovations in drug encapsulation and loading strategies, and the use of 3D printed microneedles in personalized therapeutics and diagnostics. The book also highlights recent proof concept developments, including bioinspired 4D printed microneedle platforms for pharmaceutical applications. Additionally, the book provides an overview of the commercialization and regulatory landscape for 3D printed microneedles, addressing market translation, intellectual property considerations, regulatory pathways, and innovations that enable scalable manufacturing to support successful market and patient adoption. Intended for students, researchers, and professionals in the pharmaceutical, biomedical, and healthcare technology sectors, this book delivers a structured and accessible framework for understanding both the current state and future potential of 3D-printed microneedle systems. It serves as a valuable reference for individuals interested in the convergence of engineering, materials science, and medicine, providing detailed insights into the applications, opportunities, and implications of this rapidly evolving field. Whether you are an academic scholar, an emerging innovator, or an industry practitioner, this book equips you with the knowledge necessary to engage with and contribute to ongoing developments in 3D-printed microneedle technologies.