In this article we address social acceptance in marine governance. Public support and opposition are critical to any future developments of marine areas, and are often neglected aspects. Whilst one of the main new developments in European marine areas is the increase in sites for offshore wind, social acceptance of renewable energy developments in Europe is shown to be low in a series of on-going studies. There is perhaps often a sense that renewables such as wind, wave and tidal will be 'out of sight, out of mind' when developed offshore but the empirical research evidence from across Europe suggests otherwise. People are protesting against offshore wind, and doing so very effectively, preventing and delaying the development of projects. This article articulates the term ‘social acceptance’ as a goal in marine policy implementation in European waters in general, and provides illustrations of the implications of social acceptance of offshore wind in a series of case studies. The experiences of social acceptance, together with theoretical insights, should be taken into account in future innovations for blue energy at sea, including the wind farms, but also wave and tidal devices and other technological developments.