Over recent decades Qualitative Behaviour Assessment (QBA) has been gaining acceptance as a method for assessing the lived experience of animals. It is incorporated into welfare assessment protocols for multiple species, including those developed by the Welfare Quality® and AWIN projects. QBA brings animals’ subjective experience into welfare assessment by using 15-20 qualitative descriptors to score different aspects of animals’ behavioural expressivity (e.g. relaxed or fearful), complementing animal and resource-based measures to generate a more holistic assessment of animal welfare. The Donkey Sanctuary (TDS) have pioneered the use of QBA in the practical environment to provide an evidence-base for decision-making on donkey welfare. In this presentation we will describe how The Donkey Sanctuary have incorporated QBA into their working practices in an array of scenarios. These include the assessment of individual donkey quality of life, assessment of the impact of herd structure and social groupings, as well as assessment of the impact of environmental factors on donkey welfare such as husbandry changes, different grazing opportunities and enrichment provision within the sanctuary. Outside the sanctuary, QBA has been used to evaluate the emotional experience of donkeys in European milk farms and donkey derbies, as well as provide evidence in welfare-related court cases. Incorporating QBA into all such facets of TDS work has facilitated the improvement of donkey welfare and also led to increased consideration of donkey subjective experience in people working in donkey-facing roles. This large-scale application of QBA, in combination with other forms of data-collection, illustrates the value of embedding animal welfare science into everyday practice, to develop an animal-centred, evidence-based approach to the management of donkey and mule welfare.