Plastoglobules are lipoprotein particles contained in chloroplasts and other plastids. They have long been regarded as lipid storage droplets. New results now indicate that plastoglobules actively participate in prenylquinone and other metabolic pathways. Structural work shows physical attachment of plastoglobules to the thylakoid membrane probably enabling the exchange of lipid molecules between the membrane compartments. This review will give a summary of research, past and present, attempting to elucidate the role of plastoglobules in the context of plastid function.