The automotive industry is growing faster than any other industry and neck on neck with this growth is the demand for light weight components. This is a pull factor, which is primarily influenced by the drive towards reducing fuel usage and emissions to the atmosphere. The stakes are very high in the quest to satisfy the insatiable customer hunger for reduced fuel consumption. Stringent emission regulations have also been put in place in order to mitigate the adverse effects of global warming. This has placed tremendous pressure for the increased production light vehicle components. Hence the lighter the better, and this paper focuses on the different lightweighting technologies that are being implemented in the automotive industry, and how weight reduction is vital in reducing vehicle fuel consumption and global warming. Two weight reduction methods, material substitution and topology optimization are reviewed and analyzed based on cost, strength, and stiffness. The paper also discusses the contribution that vehicle mass has on the driving cycle when compared to other parameters that affect fuel consumption.