This thesis investigates the application of surface sensitive techniques to analyse the chemical composition of metal surfaces modified by a variety of surface treatments. The first part of this thesis involves an XPS investigation of the surface chemical composition of mild steel which has being subjected to two different cleaning procedures, an organic cleaning procedure employed by the adhesive industry, and an aqueous-based formula. The switch from an organicbased formulation to an aqueous based-formula has been driven by environmental concerns. These studies conclude that the aqueous-based procedure offers superior surface cleaning properties to those of the organic clean. The crucial role played by transition metals in the cure chemistry of anaerobic adhesives was then studied. Polished copper and iron-containing mild steel substrates have been systematically modified with the individual cure components of anaerobic adhesives XPS was then utilised to study the interaction of a variety of anaerobic adhesives molecules with these substrates. The organic acids used readily form complexes with these substrates, with saccharin having a better affimty for the copper substrate and maleic acid producing a better result on the iron containing substrate. The complexes formed between the organic acids and the tertiary amines depend on the position of the substituted group, with only the para-substituted amine forming a salt at the metal interface. The copper substrate was further modified with functionalised thiols and analysed, with respect to the effect these thiols produce on the corrosion resistance of the underlying substrate XPS combined with electrochemistry was used to study polycrystalline copper modified with functionalised thiols, HS- (CH2)n-X, where X = COOH and OH The influence that chain length and immersion time had on monolayer formation was investigated, concluding that the longer chain carboxylic functionalised thiols lead to significantly better corrosion resistance for the time limits investigated.