ruhe, and Dunning basis sets, and these various basis set families are analyzed separately in the subsections that follow. A statistical survey of the results is presented in Table , broken down into the three subsets that were described in Section 3 .4, namely, hydrogen-bonded complexes, dispersion-bound complexes, and dimers with mixed-influence interactions. As with the SAPT0 assessment in Section 4 .1, error is measured relative to CCSD(T)/CBS benchmarks. 82 4.2.1. Karlsruhe Basis Sets. Errors for XSAPT + MBD using the Karlsruhe "def2" basis sets are plotted in Fig. , where the double-, triple-, and quadruple-ζ basis sets have been grouped together by color. Clearly, the double-ζ errors are much larger, exceeding 1 kcal/mol in many cases and typically 1-3 kcal/mol larger than what is obtained in more complete basis sets.