This study estimates grower benefits of Roundup-Ready (RR) weed management programs and how weed-resistance concerns and resistance-management practices affect those benefits. Direct survey methods were used to elicit grower valuation of pecuniary and non-pecuniary benefits. We illustrate a hedonic strategy combined with principal component analysis to address part-whole bias present in previous assessments of non-pecuniary benefits of RR crops. Based on a national telephone survey of 1,205 growers, the mean reported benefit of RR relative to conventional seed varieties was more than $20 per acre for corn and soybean growers and about $50 per acre for cotton growers. Growers concerned about weed resistance reported lower benefits, but this effect was statistically significant only for cotton growers, reducing their perceived benefits by about 20% ($10 per acre). Use of a residual herbicide and annual rotation of herbicides are two practices to reduce the risk of weed resistance. Corn growers using residual herbicides perceived lower, though still positive, benefits. Soybean growers rotating herbicides perceived benefits to be higher. Growers more concerned about herbicide application costs and crop safety report lower benefits, while those more concerned about the flexibility of timing herbicide applications report higher RR benefits.