The effects of Fe buffer layer on the microstructures and GMR property of magnetron sputtered Co/Cu multilayers were studied. The main focus was to systematically identify the types of microstructural features present in the multilayers and to determine their characteristic length scales via qualitative and quantitative microstructural characterisation techniques. Both diffraction and imaging techniques were used to extract useful information on layering and crystallographic structures of the materials. This has provided an insight into the structure-property relationship of the materials system. Co/Cu multilayered samples grown with iron buffer layers were found to display better structural coherency and layering quality as compared to those grown without the iron buffer layers. The high GMR effect as demonstrated by these multilayers was associated with highly correlated interface profiles, sharp columnar grain boundaries and high degree of lateral coherency in columnar grain growth.