This paper critically considers the emerging idea of marine spatial planning as part of the wider debates associated with the social reconstruction of the marine environment and the rethinking around the conventional boundaries of land use planning. First, the paper seeks to define the contemporary understanding of the marine environmental agenda, following Hannigan's (1995) social constructionist perspective. Second, it traces the evolution of thinking towards the concept of marine spatial planning. This locates the discussion within the current European discourse of spatiality, and strategies for the conservation and sustainable development of the marine environment, together with the evolving ideas associated with the practical management of coastal areas. The argument presented here is that if as a society we are successfully to reconstruct a solution to the perceived marine problem then a paradigm shift is required in terms of how we socially reconstruct the problem. It argues that the current incremental extension of terrestrial land use planning controls over aspects of the marine environment, together with the advocacy of marine spatial planning, requires a much more critically robust theoretical understanding so as to encompass the rapidly changing agenda of change.