Extension programs in Australia are encouraging farmers to adopt integrated weed management (IWM) practices, in order to delay the development of herbicide resistance in weeds infesting cropping land. Logistic and Tobit regression models were developed and used to analyse, survey data from Western Australian grain growers. Factors shown to influence IWM adoption included perceptions of IWM practices and expectations about the future of the herbicide resource. The results were consistent with the prior that farmers regard IWM as an information-intensive package of techniques, and that extension may have the potential to increase the rate of adoption.