Organic molecular adsorbates on a metal surface drastically changes the physical and chemical properties of the surface. This is promising for molecular surface modification. Organic molecular adsorption can be used to design surfaces with a large variety of properties. By carefully choosing molecular with respect of molecular size, functionality, anchoring groups, packing density, flexibility and mobility, surfaces with unique properties suitable for specific requirements can be built up. Some molecular adsorbates are ideal model systems for detailed studies of chemical and biological interfacial reactions, other works as collectors in mineral flotation and could be used for recycling of the platinum group metals. Long tailed thiols and disulfides have been shown to form Self Assembled Monolayers on gold, silver and copper. The sulfur-metal link is strong and depending on the choice of functionality, surfaces with many different the properties can be prepared. The thiol-Au system has carefully been well characterized and several different applications have been published lately. It would be interesting to find new types of stable monolayers with complementary properties. Phosphines are promising candidates for organic monolayer architecture on metallic support. We have studied Tricyclohexylphosphine adsorbed on gold and rhodium to collect information about binding strength to the surface, molecular orientation, packing density and stability. The physical and chemical properties of phosphine organic molecular adsorbates are discussed.