This chapter provides perspective on the routes of vaccine administration, comparing invasive and noninvasive delivery methods. We begin with an analysis of the most frequently used routes of administration: invasive, such as traditional needle-based injections (intramuscular and subcutaneous) and noninvasive, including oral and intranasal routes. We discuss recent advancements, for example, aerosols and jet injectors, as well as other novel administration methods for immunization such as improved mucosally-administered vaccines. Finally, we provide an update on how different delivery methods can impact consumer (vaccine recipients) compliance rates and vaccine availability (e.g., cold chain logistics in areas of the world with infrastructure limitations) from the perspectives of both the vaccine provider and the vaccine recipient.