Bill Kerruish worked in a West Australian Forests Department's forest assessment crew before commencing study at the University of Western Australia and the Australian Forestry School in Canberra. He commenced work in 1962 with the Logging Research Unit in the Forest and Timber Bureau, Canberra, focussing on mechanising pine thinning operations. In 1972 he spent a year with the Swedish Logging Research Institute studying mechanised harvesting. In 1975 CSIRO incorporated the research activities of the Forest and Timber Bureau into the Division of Forest Research and Bill assumed leadership of a revitalised Harvesting Research Group. In 1986 he and CSIRO forest economist Bill Rawlins put together a major cooperative research and development project, The Young Eucalypt Program, involving the Victorian and Tasmanian forest services and the industry associations in those two states, to explore new operational technologies to increase the productivity of the faster growing native forests. The research, which focussed on thinning, harvesting and utilising young regrowth eucalypts, underpinned industry development in those fields over the next 20 years. On retirement from CSIRO in 1997, Bill Kerruish continued to run the collaborative CSIRO/Industry Forest Technology Program, and manufactured and marketed stem injection equipment for thinning regrowth.