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Assessments of the palatability of rodenticide baits are usually conducted in the laboratory but little is known of the value of such tests as determinants of the potential performance of formulations in the field. Field bait acceptance tests conducted earlier were either unduly time-consuming or failed to take account of aspects of rodent behavior in relation to baiting regimes which make the interpretation of results difficult. This paper describes a novel, cost effective technique for assessing the palatability of baits in the field and the use of the new method to compare the acceptance of three commercial formulations, containing either difenacoum or brodifacoum, with that of an EPA approved challenge diet. No statistically significant differences were found in the acceptance of the three baits and the challenge diet at three farmsteads harboring infestations of Rattus norvegicus. Similar results were obtained in equivalent laboratory choice tests conducted following an established protocol. A comparison of results from the two environments bestows confidence both in the practical value of the laboratory test method and in the likely performance of the baits when used for rodent control operations. Wider possible uses of the field test methodology are discussed.