Perfluorocarbon (PFC) nanoparticles can serve as a platform technology for molecular imaging and targeted drug-delivery applications. These nanoparticles are approximately 250 nm in diameter and are encapsulated in a phospholipid shell, which provides an ideal surface for the incorporation of targeting ligands, imaging agents and drugs. For molecular imaging, PFC nanoparticles can carry very large payloads of gadolinium to detect pathological biomarkers with magnetic resonance imaging. A variety of different epitopes, including alpha(v)beta(3)-integrin, tissue factor and fibrin, have been imaged using nanoparticles formulated with appropriate antibodies or peptidomimentics as targeting ligands. Lipophilic drugs can also be incorporated into the outer lipid shell of nanoparticles for targeted delivery. Upon binding to the target cell, the drug is exchanged from the particle surfactant monolayer to the cell membrane through a novel process called 'contact facilitated drug delivery'. By combining targeted molecular imaging and localized drug delivery, PFC nanoparticles provide diagnosis and therapy with a single agent.