Organized monolayers with the water soluble metal complex dyad Rh-III(dc-bipy)(2)-(Mebipy-CH2-CH2-Mebipy)-Ru-II(phen)(2)(5+) have been formed at the air/water-interface by cospreading with stearic acid as lipid anchor. From the surface pressure/area isotherms it is concluded that the dyad is kept at the air/water interface by interaction with the stearic acid. According to the reflection spectra of the mixed monolayers of the dyad cospread with stearic acid, no loss of the dyad into the aqueous subphase is observed with increasing surface pressure. A structural model with two coexisting phases is proposed, one of which consists of stearic acid with dense-packed dyad molecules underneath, the second phase being composed of stearic acid and a multilayer of dyad underneath.