Spatial planning policies are fundamental blocks for the implementation of sustainable development goals. Still, despite the growing adoption of environmental proxies, as it is nature-based solutions, the study of their institutionalization in policy and spatial planning is in the early stages. Simultaneously, the use of discursive and interpretative methods to unfold the social structures related to environmental issues is growing, nonetheless, their application is more common to supranational narratives. This article proposes a conceptual and methodological approach to using critical discourse (...) analysis for studying the institutionalization and conceptualization of nature-related issues in policy and spatial planning at national and local levels. This is done by discussing the ontological relations between the discursive institutionalist theory and critical discourse analysis as a methodology. It contains four main stages: clarifying the analytical focus; mapping policy and planning documents; analyzing macro discourse, which includes critical textual analysis, text-type analysis, and intertextuality analysis, and, at last, the fourth phase, interpretation within the institutional context. It provides a tool for researchers less familiar with linguistics but interested in performing discourse analysis to understand the integration of environmental narratives within policy and spatial planning. (shrink)