The WelFur project aims at the development of on-farm welfare assessment protocols for farmed foxes (the blue fox [Vulpes lagopus], the silver fox [Vulpes vulpes]) and mink (Neovison vison). The WelFur protocols are based on Welfare Quality® (WQ) principles and criteria. Here, we describe the WelFur protocols after two years of developmental work. Reviews for each of the 12 WQ welfare criteria were written for foxes and mink to identify the welfare measures that have been used in scientific studies. The reviews formed the basis for potential measures to be included in the WelFur protocols. All measures were evaluated for their validity, reliability and feasibility. At present, we have identified 15 fox and 9 mink animal-based (or outcome-based) welfare measures, and 11 and 13 input-based (resource-based or management-based) measures. For both foxes and mink, each of the four WQ principles is judged by at least one criterion, and seven out of the 12 criteria include animal-based measures. The protocols will be piloted in 2012. Using the WQ project and protocols as a model has been a fruitful approach in developing the WelFur protocols. The effects of the WelFur protocols will provide benchmarks from which the welfare of animals on European fur farms can be assessed.