Abstract: Capillary electrochromatography (CEC) is a developing technique that combines the advantages of conventional liquid chromatography (LC) with those of capillary electrophoresis. The key difference between LC and CEC is that the latter utilizes electro-osmosis to transport the mobile phase through a column, rather than hydraulic flow as in LC. As a result of the plug-like flow profile of electroosmosis, CEC has the potential to be more efficient than LC. This article deals with the types of packing materials used for CEC separations and their influence on efficiency. Special attention is given to the present status of monolithic CEC, and its future prospects. (C) 1999 Elsevier Science B.V. All rights reserved