New review paper published in Electrochemistry Communications. Energy-efficient technologies for the remediation of water and the generation of drinking water are essential to sustainable technologies. However, we cannot have sustainable energy technology without sustainable water remediation (and vice versa). Among many possible applications, large-scale seawater desalination is a much-needed step towards large-scale hydrogen generation via power-to-gas. However, this can only be considered sustainable when done effectively and energy-efficiently. Electrochemical desalination technologies are promising alternatives towards established methods, such as reverse osmosis or nanofiltration. In the last few years, hydrogen-driven electrochemical water purification has emerged. This joint Israeli-German review article explores the concept of desalination fuel cells and capacitive-Faradaic fuel cells for ion separation. This work was done in collaboration with the research teams of Matthew Suss and of Yuri Gendel (both at Technion, Israel).