The ability of clip shaped molecules based on the building block diphenylglycoluril to form complexes with dihydroxybenzene guest molecules has been studied in detail. The binding strength of these complexes can be varied over a wide range (K-a approximate to 0-10(5) M-1), by applying small modifications in the host or the guest molecule. It is found that the complexation is a combination of different effects, viz., hydrogen bonding, pi-pi stacking interactions, and a cavity effect.