This chapter outlines the relevance of considering nature relatedness in research on the influence of environmental factors, such as green spaces, on well-being outcomes. It provides an overview of previous research that has examined nature relatedness both as a predictor of well-being sub-domains and as an outcome itself. The chapter also discusses different methodological approaches to measuring nature relatedness and the related concept of connectedness to nature. It considers three components of nature relatedness: the affective or emotional aspect, the cognitive or mental aspect, and the conative or action-oriented aspect. The chapter also emphasises the importance of capturing the role of childhood nature experiences in shaping adult perceptions of the natural environment. In addition, the chapter provides an analysis of nature relatedness across different life course phases and socio-economic classes within the sample. The life course phases considered are young adult, family, midlife, and senior phases. The socio-economic classes include higher-grade professionals, lower-grade professionals, routine sales and service workers, and blue-collar workers.