A series of crystalline metal glycerolato complexes has been prepared. The preparation of the cobalt, zinc, manganese, and iron complexes [(1 )-(4)] was achieved by heating (above 110�) glycerol with metal acetates, carbonates, oxalates, oxides, or hydroxides. The structure of (1) has been determined by X-rays and contains Co-O-Co-O and Co-O-C-C-O rings. X-ray powder diffraction and i.r. data are given for (1)-(4). These show (1) and (2) to be isostructural and that (3) and (4) are variants of these. The insolubility of (I), (2), (3), and (4) is in accord with their polymeric nature.