This chapter provides a review of the use of various dendrimer families in drug-delivery applications. The first part gives a brief introduction to the field of dendrimer science, also covering the synthesis of the most commonly used dendrimers. The second part provides a description of the chemical, structural, and physical characterization of dendrimers along with a brief description of various techniques employed, with nuclear magnetic resonance, matrix-assisted laser desorption/ionization time-of-flight, and microscopy on dendrimers described in more detail. Special emphasis is given to highlight the interplay between chemical features (repeating unit, end groups, and size) and properties. The last part provides a more detailed and in-depth overview of various dendrimer-drug conjugates and their characteristics in drug-delivery aspects.