**4. Discussion**

General causes of food waste at retail level have been addressed in the literature on an aggregated level [24] and the store owners' and store managers' perspective on food waste have been examined [19,21–23]. Nevertheless, there is a lack of research that explores the knowledge and approach of frontline employees and also studies where qualitative and detailed quantitative data are combined [24,25], as well as more in-depth analyses of food waste at the retail level [33,34]. In this study, frontline employees' perspective on cases of and measures to reduce waste was studied and a mixed methods approach was adopted, using data from interviews and observations and in-depth analyses of waste figures. This

resulted in new insights into food waste at supermarkets. The key findings are that employees with experience and mandate are crucial for reduced food waste. Furthermore, when developing waste reduction strategies, detailed knowledge about different products and an understanding of their respective causes are required. Based on the employees' point of view, four main themes explain the causes of food waste: policy, practice, people and product. The four main themes and their respective sub-themes are illustrated in Figure 2.
