This article looks at the history, development, and therapeutic and commercial validation of the use of nanotechnology for drug delivery. The first technology addressed is NanoSystem's and later Elan's, market-leading NanoCrystal technology; details are provided of the drugs that have successfully used this, and of the many deals that have involved access to it. An outline is also given of the related crystalline technology offered by Dow Pharma, and by others. The two other nanotechnologies discussed are liposomal drug delivery (with information on the deals that have concerned this), and Abraxis' nanoparticle albumin-bound (or nab#8482;) technology. Potential future developments are also considered.