Supercritical Fluid (SCF) technology is now considered as a very innovative and promising way to design particles, especially for therapeutic drug formulation.(1) The advantages of SCF technology include use of mild conditions for pharmaceutical processing (which is advantageous for labile proteins and peptides), use of environmentally benign nontoxic materials (such as CO2), minimization of organic solvent use, and production of particles with controllable morphology, narrow size distribution, and low static charge(1). SCF technology is making inroads in several pharmaceutical industrial operations including crystallization, particle size reduction, and preparation of drug delivery systems, coating, and product sterilization. It has also been shown to be a viable option in the formulation of particulate drug delivery systems, such as microparticles and nanoparticles, liposomes, and inclusion complexes, which control drug delivery and/or enhance the drug stability. This review describes the recent advances in the use of SCF technology for particle engineering and for the preparation of drug delivery systems.