Source rocks of the Aptian play an important role in petroleum systems operating off the west coast of Africa. Further south, Aptian source rocks are a proven component of a petroleum system described in the Bredasdorp Basin, a sub-basin of the greater Outeniqua Basin. It has been shown that these Aptian source rocks have supplied oil to the Cretaceous sands of the producing Oribi oilfield and its satellite fields. Aptian source rocks have also been intersected by numerous exploration and scientific boreholes in other sub-basins of the greater Outeniqua Basin, and off the west coast of South Africa in the Orange Basin. Data from these wells suggest the regional development of good-quality Aptian source rocks in the deeper parts of the Orange and Southern Outeniqua basins, possibly on a basin-wide scale. In the Orange Basin, no Aptian source rocks were intersected in the boreholes drilled in the northern part of the South African sector. However, further north, in the Namibian sector of the basin, over 100 m of good-quality Aptian source rock was intersected in the Kudu wells. To the south, at about 31 degrees S, organic carbon rich intervals a few tens of metres thick have been intersected in a number of boreholes. Here, the kerogen is largely gas-prone, with some thin intervals of shale capable of producing oil. Intersections of the Aptian in boreholes south of 32 degrees S demonstrate how the source quality can be expected to improve from a proximal to more distal position. A thin, high total organic carbon (TOC), gas-prone interval in the most proximal position improves in quality and thickness to become up to 140 m thick, capable of generating wet gas and small amounts of oil. The Deep Sea Drilling Project (DPDS) 361 borehole, located to the southwest in the Cape Basin, intersected layered dark grey and black anoxic Aptian shales with very high TOC, with alternating marine and terrigenous influence. The hydrogen indices of over 500 mg HC/g TOC from some layers are clearly indicative of oil potential. There is thus a strong case for the regional development of a good-quality source rock within the Early Aptian succession in the deeper parts of the Orange Basin. Burial history studies show that Aptian sediments should be in the oil window in large areas to the west of the basin depocentre. The Early Aptian source rock in the Bredasdorp Basin has been well described. Here it can be over 200 m thick and occurs over a large areal extent. The organic material is largely Type II with a Type I component. Early Aptian source rocks have also been intersected in the Pletmos Basin further to the east, where the organic-rich interval is over 80 m thick in places. There is strong seismic evidence that this source interval should be well developed in the greater Southern Outeniqua Basin to the south of these two inboard basins. Burial history studies in this large basin show that the Early Aptian interval is sufficiently mature over large areas to have generated and expelled oil.