The incorporation of poly(ethylene glycol) (PEG) chains at the focal point of dendrimers results in customizable platforms where the careful selection of the PEG length, the nature of the peripheral groups, and the structure and generation of the dendritic block entail materials for specific applications in the biomedical field. In this focus article, the synthesis, properties, and biomedical applications of PEG-dendritic block copolymers are discussed with examples in drug and gene delivery, tissue repair, and diagnosis.