The phased product development approach can be applied advantageously to develop and manufacture automotive microsensors. The phased approach involves a multifunctional team from innovation to development to eventual production and maintenance phases. The key advantage of this approach is the shortened development cycle and fast product introduction, while minimizing waste of resources and lowering risk of product failure. When applied to the product cycles of automotive sensors based on micromachining technology, this approach elucidates several critical considerations. In particular, since industrial application of micromachining technology is still at the infant stage, standards and design rules are not firmly established. Therefore, several important activities must be initiated simultaneously from the start of the innovation phase, which proves to be crucial to the prudent decision of technology alternatives and sensor system configuration. The use of a multifunctional team, as mandated in the phased approach, enables coherent development and optimization of the sense element, the fabrication technology, the packaging approach, the interface circuit configuration, and design features that allow efficient test and assembly flow. Also, with intermediate milestones within each phase, risk assessment and necessary midcourse adjustment to technology trade- offs can be both timely and accurate. Accelerometers, one of the most developed micromachined sensors, serve as representative examples that illustrate how the phased approach can benefits the commercialization of the newly established and rapidly expanding field of micromechanics.