Electrochemical and photochemical investigations of amphiphilic 13-membered azobenzene crowns have shown that, in solution, Z <-> E isomerization takes place for both the free crown ether and also for complexes with metal ions. Evidence for the formation of a new 1:2 (ligand:Na+) complex is presented. Monolayer Langmuir-Blodgett (LB) films on indium-tin oxide electrodes exhibited a stable voltammetric response corresponding to the cis isomer. Significant differences were found for both the photochemical behavior and the ion selectivity between the solution and solid phases. Some indications of electrochemcial recognition of Na+ were found for some LB films. This was evident from a shift in the voltammetric potentials and in the peak current versus scan rate dependence.