For more than a decade, itaconic acid (methylene succinic acid) has been one of the most promising bio-based platform chemicals. The reliable availability in the market, combined with a competitive price, makes the implementation of this molecule as a building block very interesting, also from a commercial point of view. In addition, itaconic acid being exclusively produced by biotechnological processes, is not a mere drop-in molecule. As it is not commercially available via classical chemical routes, it does not compete with the exactly same and, in most cases, cheaper petroleum-based building blocks, which is usually very challenging. But even more important, itaconic acid allows for novel chemistries and applications that cannot be achieved with the established petroleum-based building blocks. In this respect, itaconic acid has been used as an alternative monomer in radical polymerization. However, since itaconic acid is a dicarboxylic acid, it has also been explored in polycondensation reactions with a wide range of applications, spanning unsaturated polyester resins, coatings, medical applications and additive manufacturing. This work critically reviews the progress in itaconic acid-derived (poly)condensation polymers since 2016. In addition, the sustainability of this promising building block is discussed.