Analysis of more than 700 modern continental sedimentary basins that are both endorheic (internally drained) and exorheic (externally drained) and cover a wide range of climatic and tectonic settings shows that sedimentation is dominated by distributive fluvial systems (DFSs). Facies distributions on DFSs are different from those of rivers in degradational settings, yet rivers in non-aggradational settings are commonly used to develop fluvial facies models. DFS rivers typically decrease in size downstream, are not confined to valleys, and form a radial pattern from an apex. Confined rivers are present in specific locations in sedimentary basins, including basin axial positions, areas between adjacent DFSs, and valleys incised into the DFS. DFSs and adjacent axial fluvial systems develop in a predictable manner that allows interpretation and prediction of fluvial architecture at the basin scale.