Excess molar enthalpies H-m(E) of dimethylcarbonate, diethylcarbonate or propylene carbonate + trans-l, 2-dichloroethylene, + trichloroethylene, and + tetrachloroethylene, respectively have been determined at 298.15 K using an LKB flow-microcalorimeter. Experimental data have been correlated by means of the Redlich-Kister equation and adjustable parameters have been evaluated by least-squares analysis. The H-m(E) values range from a minimum value of - 1000 J mol(-1) for diethylcarbonate + trans-1, 2-dichloroethylene up to a maximum of 920 J mol(-1) for dimethylcarbonate + tetrachloroethylene. For each series of mixtures, a systematic increase in H-m(E) with an increase in the number of Cl atoms in the chloroalkene molecule has been noted. The results are discussed in terms of the molecular interactions.