Palaeoecological and sedimentological analysis has been applied in the study of Lower Carboniferous Waulsortian 'reefs' exposed in the Manifold Valley, North Staffordshire and in the Meuse Vallley in southern Belgium. Because Waulsortian 'reefs' have similar faunal, lithological and palaeogeographical characteristics in all of their occurrences it is argued that conclusions drawn from the Manifold and Meuse Valleys are applicable to the facies as a whole. Evidence is presented to show that lithological facies previously recognised within the Belgian Waulsortian can also be recognised elsewhere, and that changing sedimentation rates can explain many of their characteristic differences. Faunal and seimentological evidence indicates that the rate of sedimentation increased as the mounds developed. It is argued that the mound sediment was produced in situ and faunal data suggests that the surface of the mounds was firm. Early submarine lithification is thought to have been an important process in producing firm substrates and in maintaining steep depositional slopes. Fabrics and lithological components suggestive of early lithification have been recognised. A general model for Waulsortian development, based on conclusions drawn in this thesis, is presented.