As the aquaculture sector grows worldwide, appropriate planning is becoming fundamental to sustain its growth and contribution to poverty alleviation and economic development. This document acts as a guide for policy-makers and those involved at all levels of planning to assist them in the formulation and implementation of sound aquaculture policies. It clearly defines what constitutes a policy, a strategy and a plan, and sets aquaculture development in the broader agendas of international development and good governance. It proposes practical steps to improve aquaculture policy formulation processes and instruments to support the implementation of policies, and suggests means for overcoming human, institutional and financial constraints to their implementation. This paper will provide valuable and practical information and guidance to aquaculture planners, in their efforts to develop, review or implement aquaculture policies for the sustainable development of the sector.