Nature-based solutions (NBS) have been widely recognised by governments in climate change and biodiversity strategies. But significant barriers exist for their large-scale implementation. Esmee Kooijman and Siobhan McQuaid, together with Profs. Mary-Lee Rhodes and Marcus J. Collier from Trinity Business School, Trinity College Dublin, and Francesco Pilla from University College Dublin, take the first step in a thousand-mile march toward market development of the sector by proposing a classification for organisations delivering NBS and categorising their economic activities.