As several of the free form fabrication processes progress with continuous process and material improvements, the feasibility of Rapid Manufacturing becomes more and more of a reality. Defined as the use of a Computer Aided Design (CAD) based automated additive manufacturing process to construct parts that are used directly as finished products and components, some of the rapid manufacturing processes are already competing with traditional processes such as injection moulding and progress is being made in applying the new technologies to the processing of metals, envisioning additive manufacture of high strength parts of unlimited complexity. While there have been quite a few successful attempts in the rapid production of complex medical implants using titanium alloys, 3D printing of sand moulds opens up yet another rapid manufacturing front, allowing for the rapid casting of aluminium and magnesium alloys. The effectiveness of such processes is yet to be researched in terms of process and product characteristics and the overall economy. This paper attempts to review some of the promising rapid manufacturing technologies for light metals processing and presents results of experimental investigations conducted to evaluate the effectiveness of the rapid casting process currently researched at the Rapid Product Development Centre of AUT University.