Pacific, metropolitan and distant-water fishing nations are negotiating a regional regime for managing the western and central Pacific tuna fishery. The regime will require an arrangement that delivers high-quality scientific advice. But regional science arrangements have often developed without the benefit of planning and without close attention to management requirements. We use the western and central Pacific fishery to highlight the types of science functions and attributes required for effective regional fishery management. In establishing science arrangements, nations will need to balance national interests, such as participation in stock assessments, against the wider interests of resource management which requires unbiased scientific advice.