Organic nanoparticles for drug delivery and imaging. A number of organic nanoparticles have been developed to encapsulate and deliver therapeutic and imaging agents. The articles in this issue of MRS Bulletin highlight applications of organic nanoparticles for therapeutic delivery and imaging, and focus on recent advances in this field. The cover shows one-, two-, and three-patch surfaces of multicompartmental particles that, because of their unique characteristics, can be selectively surface-modified based on the incorporated functional polymers. Different fluorescent labeled molecules were used on the surface and within each compartment of the particles shown, which were then imaged with a confocal microscope. Such particles can be used for drug delivery, tissue engineering, self-assembly, and novel gel formation. Image courtesy of Sahar Rahmani. See the technical theme that begins on page 219.