The ability to apply nanomaterials as targeted delivery agents for drugs and other therapeutics holds promise for a wide variety of diseases, including many types of cancer. A nanodelivery vehicle must demonstrate in vivo efficacy, diminished or no toxicity, stability, improved pharmacokinetics, and controlled-release kinetics. In this issue, Lee et al. construct polymer nanobins that fulfill these requirements and demonstrate effective delivery of doxorubicin in vivo to breast cancer cells. This Perspective explores the outlook for these nanobins as well as other technologies in this field and the challenges that lie ahead.