Abstract : Chemotherapy, the most commonly used systemic treatment for cancer suppression, invariably destroys healthy cells, resulting in side effects, stressing the need for anticancer drug carriers that preserve or enhance chemotherapy effects while minimising the intensity of adverse reactions. Nanoparticles, which may be modified to have a variety of biological features and employed in a variety of contexts, offer a safer and more effective way to deliver chemotherapy. We have discussed uses of polymer nanoparticles, dendritic polymers, micelles, liposomes and other nanoparticles that are being investigated as drug carriers. We have briefed various endogenous and exogenous stimuli that can be used to release the packed drug from the nanoparticle at specified targeted sites. Combination drug delivery systems composed of various nanoparticles aimed at delivering two or more drugs simultaneously that can give synergistic antitumor effects and decrease individual drug toxicity are also discussed. Applications of nanoparticles in certain specific cancers and nanoparticles designed for intracellular drug delivery are discussed as well.