Despite interest and willingness to apply advances in animal welfare science, it is becoming increasingly difficult to do so. This paper addresses three main areas. The first deals with economic consequences and, while recognising the cost of implementing change, highlights the importance of hidden costs in animal disease. It argues that when these costs are taken into consideration more money can be allocated to the prevention of welfare problems. The second section relates to the fact that as animal welfare science progresses, there will tend to be scientists who focus on theoretical concepts and those who focus on practical problems. This specialisation may mean that intermediate research is needed to bridge the gap between the original idea and its practical implementation. It may also mean that the scientist making the original advance may not be well placed or even interested in doing this. The final section on the difficulties of applying scientific advances makes the point that as the number of scientists in the area increases, so does the discussion of methods and results. In the long-term these intellectual exchanges obviously benefit the science, but in the short-term they slow down the implementation of findings. Scientists focus on differences in interpretation not on similarities, leading non-scientists to sometimes miss the large areas of agreement and see only uncertainty in other areas. The paper concludes by suggesting that awareness of the factors affecting the application of scientific advances will help to minimise the risks that good ideas and results are not implemented in practice.