Micropaleontologic and sedimentologic studies have been carried out on the onshore Cretaceous sediments of the Agadir and Essaouira coastal basins, and offshore deep-sea Cretaceous sediments recovered from DSDP sites 135, 137, 140, 367 and 370 off the coast of northwest Africa. Facies analysis reveals several episodes of transgression and regression in the coastal basins, suggesting a local subsidence and interplay between the rates of sedimentation and sea-level change. The Late Cretaceous transgression commenced during the Late Aptian-Albian and reached a maximum during the Early Turonian. The Late Cretaceous transgression had two major events of coastal upwelling of cold water masses during the Turonian and Maastrichtian with the production of cherts, radiolarians, non-keeled planktonic foraminifers and phosphates (Antarctic current). The Coniacian to Early Santonian was regressive, whereas the Campanian facies (keeled planktonic foraminifers) recorded a warm cycle of the Cretaceous transgression. The study has also revealed several specialized assemblages of foraminifers associated with sediment facies of particular ecologic and environmental significance. Onshore and offshore correlations reveal the evolution of the passive margin, which includes a subsidence, deep-sea circulation, variation of the calcite compensation depth (CCD), a mid-Cretaceous oceanic hiatus, and Late Cretaceous transgression in the coastal basins. These events seem more or less synchronous in nature and depict north Atlantic paleogeographic developments through the Cretaceous. The mid-Cretaceous events such as deep-sea hiatus and oceanic circulation in the North Atlantic and their extension in the South Atlantic apparently suggest a structural communication in both realms of the Atlantic Ocean, although faunal evidence indicates an earlier surface connection during Aptian to Albian. Finally in the light of published data some paleogeographic aspects are reviewed.