Appropriate dialcohols have the ability to form unidirectional ladder structures on crystallisation from solution. These assemblies are built from two internally hydrogen bonded molecular strands which are cross-linked by further hydroxy group hydrogen bonding. In staircase-ladder structures the molecules of the two strands are out of phase and linked by (O-H)(n) chains. Alternatively, if the molecules of the two strands are in phase, a step-ladder structure results where the dialcohol units are linked by (O-H)(4) cycles. Both ladder types show strong enantiomer ordering and symmetry preferences. For example staircase-ladders normally comprise dialcohol molecules of one handedness surrounding a 2(1) screw axis. New racemic dialcohols are described which form staircase-ladders. Self-resolution, guest inclusion, enantiomer ordering, and asymmetric unit phenomena are described which result in previously unobserved types of staircase-ladder assembly.