In the last two decades, biofuel research has intensified as they are being increasingly considered as a viable replacement for crude oil derivatives. In comparison to crude oil reserves, biological feedstocks for bio-fuel production are globally widespread. On the other hand, biofuel production currently brings several disadvantages, which have given rise to skepticism towards the use of biofuels as a suitable fossil energy replacement. This chapter describes seaweed’s biological advantages and disadvantages in terms of their use as an energy crop and examines global production trends of seaweeds. Furthermore, the chapter explains seaweed cultivation, together with harvesting logistics and supply chain. The chapter provides a systematic overview and explanation of conversion routes to producing biofuels and other value-added products from seaweed, backed up with experimental examples. Finally, the chapter gives detailed case studies for theoretical industrial scale processes for three different conversion routes and looks ahead to future research trends in this area.