Artificially layered materials and ultrathin films of ferromagnetic substances currently receive considerable interest in materials science. These systems often show novel magnetic properties which differ dramatically from those of the corresponding bulk ferromagnets, e. g.,unexpected magnetic anisotropies or surprisingly low Curie temperatures. Research in this field is stimulated by both scientific curiosity and potential applications in magnetic storage and sensor technology. A successful development of new storage devices and technologies requires a fundamental knowledge of the underlying physical mechanisms, in order to be able to deliberately modify the magnetic properties of a given material or system. Understanding the magnetic properties turns out to be difficult, since the altered magnetic behavior of films in the monolayer regime must generally be attributed to more than one physical mechanism. Although some of the effects appear due to the reduced dimensionality, it has been realized that crystalline structure and peculiarities in the epitaxial growth process of ultrathin films play a crucial role. This is particularly important in the case of layers built up from metastable crystalline phases, such as face centered cubic iron or cobalt. A thorough understanding of the magnetic properties of epitaxial systems thus requires a broad data base which must include structural aspects and a precise characterization of the growth process in its various stages, as well as the influence of the growth conditions. This "wide band" approach promises new and yet unprecedented insight into the links between structure, topography, morphology and magnetic behavior. As a welcome side aspect, one may expect such an approach to facilitate the comparison of results from different groups on the same system, thus helping to reduce the number of possible inconsistencies. In the following we report on our investigations and results on ultrathin fcc-cobalt films on Cu(001) substrates.