Capacitively coupled contactless conductivity detection ((CD)-D-4) has become an accepted detection method in capillary electrophoresis (CE) for a variety of analytes. Advantages of this technique over optical detection modes and galvanic contact conductivity detection include great flexibility in capillary handling and rather simple mechanical parts and electronics, as it can be performed in an on-capillary mode. Furthermore, the detection principle can be used with capillaries made of other materials than fused silica (PEEK(R), Teflon(R)), with chip-based separation technologies, or with capillaries having very small inner diameters. This review presents a discussion of the published literature on (CD)-D-4 for CE and capillary electrochromatography.