Polymeric materials formed via layer-by-layer (LbL) assembly have promise for use as drug delivery vehicles. These multilayered materials, both as capsules and thin fi lms, can encapsulate a high payload of toxic or sensitive drugs, and can be readily engineered and functionalized with specific properties. This review highlights important and recent studies that advance the use of LbL-assembled materials as therapeutic devices. It also seeks to identify areas that require additional investigation for future development of the field. A variety of drug-loading methods and delivery routes are discussed. The biological barriers to successful delivery are identified, and possible solutions to these problems are discussed. Finally, state-of-the-art degradation and cargo release mechanisms are also presented.