A contribution to harmonize water footprint assessments

•A harmonized water footprint assessment is proposed for micro- and macro- decisions.•The assessment allows for product- and water management-focused approaches.•We apply the assessment to soybean production in Mato Grosso, Brazil.•The harmonized assesment overcomes limitations of individual approaches. The water footprint (WF) has introduced a much-needed perspective for decision-makers on the use of water resources in supply chains. It has been used as a tool to assess and improve water use efficiency and water resources management, as well as inform on potential environmental impacts of water consumption in products. This paper is a contribution towards harmonizing WF assessments within decision-making contexts as they relate to their specific focus on either products or water management. First, we describe the relationship between product- and water management-focused WF approaches and their distinct perspectives, priorities and reliance on specific academic fields in relation to water resources decision-making. We then propose a harmonized WF assessment that observes both hydrogeographic and product system boundaries. We apply this harmonized WF assessment to the case of soybean production in Mato Grosso, Brazil, to illustrate how micro- and macro-level decision-making can be combined for a more complete set of policy responses affecting water resources. Our contribution aims to better highlight the strengths and limitations of individual WF approaches and assessments which can be overcome by a harmonized approach. By focusing the conversation on a more integrated assessment of water use in relation to decision-making, we show the range of different purposes and useful WF results that, together, can promote responses for greater local and global water security.