This paper locates Ecologically Sustainable Development (ESD) as the only credible overarching policy objective for contemporary planning systems and presents six key policy and governance areas where a planning system's ability to implement ESD is determined. Through the analysis of face-to-face interviews, the paper provides a snapshot of the issues and concerns of local government planners regarding the ability of the NSW planning system to implement ESD. It is found that, despite the content of aspirational documents and in the context of reform agendas that prioritise economic growth, the NSW planning system is currently not well placed to implement ESD. A degree of consensus is found regarding the particular legislative, structural and cultural factors that work to impede the implementation of ESD in NSW: an overly narrow view of the role of planning; a focus on development assessment at the expense of strategic planning; insufficient statutory weight given to ESD; and a lack of policy integration at State government level. Perhaps most significantly, given the review of planning legislation currently being undertaken in NSW, this paper identifies a package of policy and governance reform directions that together will promote more effective implementation of ESD in the future.