In this chapter, we describe the use of microneedle arrays for delivery to targets within the skin itself. Breaching the skin's stratum corneum barrier raises the possibility of administration of vaccines, gene vectors, antibodies, photosensitisers and even nanoparticles, all of which have at least their initial effect on populations of skin cells. Intradermal vaccine delivery, in particular, holds enormous potential for improved therapeutic outcomes for patients, particularly those in the developing world. Various vaccine‐delivery strategies have been employed and here we discuss each one in turn. We also describe how photodynamic therapy can be enhanced using microneedles, and explore the potential of intradermal nanoparticle deposition using microneedles.