The application of the concepts of Replacement, Reduction, and Refinement has been a key element in defining a system for the integration of animal welfare as an essential component of an experimental design Today, the importance of achieving a balance between animal welfare and scientific objectives is being increasingly expressed through regulations, guidelines, organizational terms of reference, and institutional review processes. This balance has also recently been recognized and expressed in the editorial policies of some scientific journals. In general, scientific journals exert enormous influence on the quality of experimental design and planning. An assessment of the extent to which requirement of the consideration of animal welfare forms part of current editorial policy revealed that only 24 of a sample of 46 journals that publish animal-based research require the authors to certify that the research met an ''established standard'' for the care and use of animals. Of 85 recent articles published in five journals with stringent animal welfare requirements, 25 provided no evidence of meeting an established standard. Close examination of 63 articles revealed that scientific information regarding the animals or their husbandry, or welfare information on postprocedure analgesia, was generally absent. Increases and improvements in national policies, regulations and guidelines on animal use in experimental procedures are not adequately reflected in published articles, nor is the importance of animal welfare to the quality of the experimental design.