To date, transdermal delivery has been restricted to a relatively small number of drugs with specific physicochemical properties. In this chapter, we examine the potential role of microneedle technology in broadening the range of compounds that can be delivered percutaneously. Particular attention is paid to reviewing how the physicochemical properties of a drug substance influence its penetration through microneedle‐induced micropores. In addition, we discuss the various microneedle systems that have been employed to deliver drugs across the skin. We also highlight the primary hurdles that must be overcome so that these relatively sophisticated drug delivery systems can become commercially available.