Extensions of the ideal associated solution theory which take into account intermolecular interaction and/or size factors are derived and applied to triethylamine+ CHCl3 and diethyl ether+CHCl3. Evidence is presented for non-hydrogen-bonding specific interactions between the unlike molecules in these systems. Theories that do not take this into consideration are likely to be unsatisfactory for the determination of hydrogen-bond properties. With respect to the evaluation of ?net complex formation? properties, the extensions considered do not represent significant improvements of the simple theory. The molar enthalpies of mixing of triethylamine+CH3CCl, and diethyl ether+ CH3CCl3 have been measured at 288.15 and 298.15 K.