The extent to which people see themselves as part of the natural world - known as Human-nature connectedness (HNC) – might be a key societal trait for achieving sustainable targets. A recent meta-analysis shows that reinforcing HNC can be a leverage point for enhancing citizen wellbeing and engagement in nature conservation. The analysis of 57 experimental studies documents an increase of HNC after participating in behavioral interventions involving active contact with nature (e.g., forest walks) whereas no effect was observed after indoor interventions aimed at improving knowledge about the environment or biodiversity (lectures, classroom interventions). Thus, HNC indices are positively related to human well-being and nature conservation and can be improved by simple, but carefully designed, interventions involving engagement with nature. Improving HNC may be a valuable and simple way to help individuals in industrialized countries understand and experience the interdependence between human well-being and nature conservation, at least in industrialized countries, which constitute the bulk of existing studies.