The ability of certain dialcohols to form solid‐state structures containing unidirectional hydrogen‐bonded ladders has been investigated. Two double‐stranded structures, staircase‐ladders and step‐ladders, have been identified. In each, dialcohol molecules are hydrogen‐bonded into linear strands with two parallel strands cross‐linked through additional hydrogen bonding. Staircase‐ladders are made up of (O−H)n chains of hydrogen bonds, with the molecules in the two strands out of phase with each other. Step‐ladders are formed from (O−H)4 cycles of hydrogen bonds, with the molecules of the two strands in phase. Sixteen examples of staircase‐ladder structures and twelve cases of step‐ladder structures were identified by use of the Cambridge Structural Database. A further three examples, all shown to be staircase‐ladders by single‐crystal X‐ray analysis, were synthesised. Distinct structural preferences in ladder formation can be identified. Nearly all staircase‐ladders contain only one type of enantiomer, with the dialcohol building blocks arranged around a twofold screw axis. This type of ladder is thus favoured for enantiomerically pure compounds. The preferred step‐ladder construction contains (+)‐enantiomers in one strand and (−)‐enantiomers in the other, giving two repeating centres of symmetry along the ladder axis. There are, however, many exceptions to this norm. These two ladder types are compared with each other and with those formed by organic molecules containing other hydrogen‐bonding functionalities.
