ACS ES&T Engineering and ACS Electrochemistry, this joint special issue,“Fundamental and Applied Advances in Electrochemical Technologies for Sustainable Water Treatment and Resource Recovery”, highlights how electrochemical approaches reshape water quality management and resource recovery across multiple scales. Within this collection, advances in electrochemical separation and desalination are showcased through new capacitive deionization (CDI) architectures and mechanistic tools. Contributions span bionic vein-shaped flow channels and optimized cation-exchange membranes for high-efficiency desalination of brackish water (10.1021/acsestengg. 5c00450, 10.1021/acsestengg. 5c00417), asymmetric and membrane CDI systems for targeted removal of cesium and arsenic (10.1021/acsestengg. 5c00488, 10.1021/acsestengg. 5c00657), operando ambient-pressure X-ray photoelectron …​