The results of a detailed study of the uptake of HCl by the deuterated analogue of protonated water clusters are reported. The primary uptake of HCl is found to occur by bimolecular reaction whereupon studies at a variety of pressures indicate that no termolecular process is involved. Interestingly, varied temperature studies indicate an inverse temperature dependence on the bimolecular rate constants. The discussion is partitioned between efficiency considerations of the experimentally determined kinetics and atmospheric interpretations of HCl uptake, the latter involving comparisons to mass accommodation coefficients, measured using ice films as polar stratospheric cloud mimics.