Recently, McKemmish and co-workers reported benchmark calculations on the performance of density functional theory (DFT) for thermochemistry and barrier heights, using a variety of double-and triple-ζ basis sets. Some of their conclusions are unsurprising. For example, we wholeheartedly concur that such calculations should not be performed without polarization functions. This is very old advice, 2 however, as is the suggestion that triple-ζ basis sets are needed for DFT thermochemistry. Early benchmark studies suggested that Pople-type basis sets including 6-311+G(2d,p), 6-311+G(3df,2p) and 6-311+G(3df,2pd) were appropriate for thermochemical calculations, and 6-311++G(3df,3pd) is often used as a surrogate for the basis-set limit. As such, the titular prohibition on 6-311G-type basis sets came as a surprise, given that none of the aforementioned examples were examined in Ref. 1. Pople-style basis sets have fallen out of favor in modern DFT benchmarking, 9,10 so a fresh and comprehensive look was perhaps warranted. However, Ref. 1 suggests that basis-set benchmarks and clear recommendations are unavailable in the literature, which is untrue. Unambiguous recommendations are that thermochemical calculations (including barrier heights) should employ basis sets of at least triple-ζ quality, although a composite model wherein triple-ζ single-point energies are evaluated at double-ζ geometries is often an acceptable compromise. Triple-ζ basis sets are also required to obtain converged intermolecular interaction energies, unless counterpoise correction is employed. In all cases, quadruple-ζ basis sets should be used to establish the basis-set limit with certainty, although extrapolation using doubleand triple-ζ results also works well. In short, there are copious basis-set recommendations for use with DFT calculations, backed up by extensive benchmarking, not least for thermochemistry. We agree with the critique (implicit in Ref. 1) that the 6-31G(d) basis set remains too widely used in 21stcentury quantum chemistry, although that suggestion has been made before. We furthermore concur with the recommendation to use def2-TZVP for routine thermochemical calculations. That said, we reject the blanket admonition to avoid all polarized 6-311G-type basis sets in that capacity, and we do not believe that the data presented in Ref. 1 justify such a conclusion.