This paper seeks to analyse the role of institutions and entrepreneurship in the field of green innovation in Wales. Green innovation can be defined as innovations in environmentally responsible products and services that are both sustainable and contribute to reducing the impact of greenhouse gases (GHG) upon the environment. The paper adopts a standard co-evolutionary perspective that will take into account differences in the history of firms and institutions in the emerging renewable energy sector. However, the paper finds soime problems with the standard theoretical accounts in the literature.. Here, and based on case study analysis, the paper investigates the extent to which technologies and institutions can be seen as co-evolving systems and the degree to which co-evolutionary thinking and its elements are present in government policy for green innovation. The test is applied in the mainly rural regions of Wales where green innovation is pronounced.