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Erldunda Station has long been known as the centre of rabbit distribution in the Northern Territory. An estimated 23,000 warrens exist on the 2932km2 Station, 7.8/km2. Patchy distribution of suitable habitat and warrens and infrequent favourable breeding periods at the northern edge of rabbit distribution in Australia suggested localised eradication of patches by ripping and fumigation could be practical and economic. After 4.5 years over 4000 warrens have been ripped on 270 km2 of preferred cattle And rabbit habitat by Station staff. The costs of ripping were about $250 /km . In 1990 rabbit numbers after three good years were 208 /km2 in untreated areas and 1.1/km2 in treated areas. Drought conditions in 1990 and 1991 with a heat wave in Japuary 1991 caused rabbit numbers on untreated areas to decline to about 1 /km , similar to the estimated 2/km2 on treated areas. Initial success and assessment of the enormousness of the task prompted development of a cooperative program whose aim was to demonstrate the feasibility and economic benefits of large scale localised eradication and the advantages of cooperative effort. A 10 year project coordinated by the CLMA plAns to eradicate rabbits and monitor costs, success and benefits on a 250 km4 area on adjoining Erldunda, Lyndavale and Mt Ebenezer Stations. Pastoralists provide equipment and staff, NSCP funds for fuel and labour, anc NT Government Depts. monitor the program. Baiting and ripping of the 250km area began in November 1990 and were completed in 15 months. Initial follow up fumigation was mostly complete by April, 1992. Cost of ripping over 3500 warrens was calculated at $474/km . Administration costs, clearly identifiable in the larger project, are not normally recognised in small scale projects. On -going costs will mainly be annual fumigation of active rabbit warrens by Pastoralists. Baseline vegetation survey of selected sites in ripped and untreated areas was completed in 1991 and will be repeated annually. Economic data gained over 10 years will assess cost of increased production of both vegetation and stock as well as ecological recovery. Integration of warren ripping with natural or introduced biological control of rabbit populations should allow long term reduction of rabbits and regeneration of pasture and habitat in some land systems. Anticipated biological and genetic controls may be required for land systems where warren destruction may not be economically possible.