We present structures obtained with numerical optimization techniques capable of efficiently channeling light at a fraction of the length of a conventional taper. These results could open the way to novel designs in ultra-short light injection devices. We also consider the rather different problem of how to optimise the transmission through a photonic crystal bend. We show how, using a deterministic global optimisation algorithm, novel optimal geometries can be obtained leading to considerable performance improvements.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.