Excess volumes have been measured by means of a continuous-dilution dilatometer for (N,N-dimethylacetamide + benzene or toluene or o-xylene or m-xylene or p-xylene or ethylbenzene or styrene) at the temperature 298.15 K. V-m(E) values are negative over the entire range of composition for all the binary mixtures. V-m(E)(minimum) and V-m(E)(x = 0.5) values of this series decrease in the sequence : C6H5CH=CH2 > C6H5CH3 > p-C6H4(CH3)(2) > C6H6 > m-C6H4(CH3)2 approximate to o-C6H4(CH3)(2) > C6H5CH2CH3. The results were compared with the results for binary mixtures containing other polar liquids, and show that there are quite strong interactions between N,N-dimethylacetamide molecules and aromatic-hydrocarbon molecules.