Seaweed has captured the imagination of government, corporations and the public worldwide because of its potential for productive, environmental and livelihood impacts. Carrageenan seaweeds represent more than a quarter of all seaweeds produced globally, and are produced in tropical regions around the world, although mostly in Indonesia and the Philippines. Indonesia has sought to expand the industry through ambitious development plans, and rural Indonesian communities on coastlines across the country have embraced the new livelihood activity. This chapter introduces the book and outlines the structure of it: Part I traces the carrageenan value chain from the global to national to provincial levels. Part II takes a detailed look at the ways that rural communities in one Indonesian village have reshaped their lives around seaweed production through chapters on agrarian transformations, access to sea space negotiations, farmer decision-making within environmental, social and economic constraints, the role of women and casual labourers in the industry and the marketing of seaweed through social networks.