Rh-Cu supported on alumina were selected for the dehydrogenation of cyclohexanol. Highly dispersed Rh-Cu supported on alumina were obtained and characterized after reduction. The metallic surface area was determined by frontal H-2 chemisorption and by N2O decomposition followed by TPR. The TPR method for surface oxide reduction after exposing the catalyst to N2O decomposition for the determination of the active phase is in good agreement with the frontal H-2 chemisorption method on rhodium, copper and bimetallic catalysts. The temperature and time exposition are important parameters for a complete oxidation of the monolayer, in particular for lower concentration of copper. An exposition time of 20 h is needed to complete a monolayer oxidation. Metallic copper is oxidized to Cu1+ and CU2+ although not all Cu2+ is reduced to Cu1+ without oxidation of a sublayer. For the bimetallic catalysts Rh-Cu a complete monolayer was attained. The TOF values were calculated based on the total active sites which give correct interpretation of the activity. The activity decreases when copper is added to rhodium which was attributed to an ensemble effect. For lower contents the selectivity of ketone was enhanced, which could be explained by simultaneous geometric and electronic effects. The selectivity on the monometallic catalysts prevails toward cyclohexene formation, indicating strong influence of the acidic sites, However, for the bimetallic catalysts it changed drastically toward dehydrogenation. The second metal affects the surface sites enhancing the metallic or bimetallic formation for dehydrogenation. This phenomena explains the electronic effect on bimetallic Rh-Cu systems.