This paper presents the state of the art of different wood densification processes as one emerging process technology. The main principles for the processes are discussed, such as bulk and surface densification, bending, moulding of shells and tubes, as well as methods for reducing the shape memory effect of densified wood. The main challenges are in the field of scaling up to industrial applications. To provide a better understanding with this regard, some relevant scientific results are presented. Furthermore, the discussion considers the contribution of thermo-hydro and thermo-hydro-mechanical processes to a sustainable and low-carbon economy.