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It has been shown that Raman spectroscopy can be used in the in-situ investigation of electrodeposition processes. In thiourea (TU) containing systems, Ag deposition takes place through a strongly adsorbed TU layer; while in cyanide containing systems, Ag deposition is envisaged as the removal of the central atom of a coordinated silver cyanide complex adsorbed at the surface. It is shown that the controlled deposition of Pb, T1, Zn, Ni, Co, Fe and Cu onto roughened (and in some cases smooth) Ag electrodes leads to new surfaces which show enhanced Raman scattering of adsorbates. The SERS mechanism is discussed briefly. SERS and electro-chemical studies show that TU forms surface complexes with anions through its NH₂ groups; the surface complexes have very different adsorption characteristics in neutral and acidic solutions. The nature of the adsorbed species in both cyanide and silver cyanide complex containing solutions has been studied. SER spectra and a possible model for adsorbed water molecules are presented.