Regional integration is to progress to an advanced and critical stage in SADC. With the launch of the SADC free trade area having taken place successfully in 2008 the next step according to the SADC RISDP is the customs union stage. This stage involves deeper integration as well as more cooperation amongst Member countries and to some extent will involve ceding of sovereignty to a supranational body that will be tasked with the administration of the customs union. With the lack of cooperation that was showed by some SADC countries during the implementation of the SADC FTA one doubts whether SADC countries will indeed cooperate during the customs union phase. Different levels of development, divergent trade policies and overlapping membership into other RECs pose a significant challenge into the formation of a SADC customs union. Looking at the challenges confronting the formation of the SADC customs union it would seem as if it is all gloom and doom. However one lesson picked up in all regional integration initiatives in all regions of the world is that significant challenges will always exist; what is important is that Member countries need to show full commitment and focus on the bigger goal they seek to achieve as the region. SACU the world’s oldest customs union is constituted by SADC Member countries. With the problem of overlapping membership SACU is both an obstacle and a solution for SADC depending on which view one holds. SACU can be seen as an obstacle because if SACU was not there perhaps the problem of overlapping membership would not be the way it is. Currently only one SADC country is not affected by the problem of overlapping into various other RECs. If SACU was not there the number of countries not overlapping would be perhaps six countries. On the other hand one can choose to look at SACU as a solution to the establishment of the SADC customs union under the circumstances that currently prevail in SADC. SACU can be used as a basis for a SADC customs union by having all other SADC Member that are ready to join the customs union accede into SACU and whilst others that are not ready still work on their policies and join latter when they are ready to do so. This is referred to as ‘variable-geometry’; a principle that has been successfully implemented in the EU over the years. However taking a close look at SACU one realises that there is still lot of work to be done within SACU to have SACU ready for expansion.