Microstructured polymer optical fibres [mPOF] were first developed in 2001, and have attracted attention in part because the range of fabrication techniques possible with polymers has allowed novel structures to be made that cannot be made simply in other materials. Their material properties also offer attractive possibilities as polymers can contain a much larger variety of dopants than glass. In this article, we review progress on some of the major challenges of this technology: particularly the need to reduce fibre losses, and report on some recent developments including the fabrication of the first hollow core mPOF. Some initial investigations into changing the material properties are reviewed.