In this chapter, we have given an overview of a range of biomass-based polymers prepared through polycondensation chemistry. This is by no means an exhaustive summary of available starting materials and polymers. Still, it is clear that this rapidly expanding field of research opens up new synthetic pathways to performance polymers with exciting novel properties. Some of these biobased polycondensates can rival conventional polymers from petro-chemistry in terms of mechanical and chemical performance and a limited number have already found their way to the market place. Further development of bio-refining processes is expected to improve the availability and economics of the discussed starting materials and polymers. Several of the presented polymers can be produced in existing process equipment with only minor adjust ments. Typically, improved temperature control and an inert atmosphere are required to prevent degradation and discoloration of the bio-based products. In addition, more sustainable and milder synthetic routes as well as more effective catalysis are necessary to make optimal use of biomass, constituting stimuli for new research into the field of step-growth polymerization.