A commercially available surfactant-specific electrode has been employed to investigate the dilution behavior of hexadecyltrimethylammonium bromide/hexadecanol gel phase (L-beta) dispersions. Initial measurements on known surfactants demonstrated that the electrode gave reliable data. The structure of the gel phase and the extent to which it swells in water were established by optical microscopy and X-ray diffraction. Surprisingly large nonequilibrium concentrations of monomeric hexadecyltrimethylammonium bromide occur in gel phase dispersions immediately after dilution, which can reach the critical micelle concentration of the pure surfactant. Much lower levels occur after some time (hours to days). These time-dependent changes are likely to be important in the practical applications of gel phase surfactants as emulsion stabilizers or in conditioning products.