During the year and a half of preparation for the Untnmed Ri Expedition (Caves $ Caving 29 p. 29) a lot of time was devoted developing the techniques we would use to explore the roaring wh waters of Nare. We finally left for New Britain with a whole new set caving rules and hardware which would not be out of place in an Indi Jones movie. The first serious work to tackle this new problem in caving wa pioneered by the French in 1978 after the discovery of the Nare. M and Kavakuna - all big river caves with flows of 15-20 cumes. We tir out these techniques on the white water rivers of north Wales. ma some improvements and tested some new ideas. This articles is a summary of our research and experience.