Aerospace applications require a range of chemical sensing technologies to monitor conditions related to both space exploration and aeronautic aircraft operations. These applications include leak detection, engine emissions monitoring, fire detection, human health monitoring, and environmental monitoring. This paper discusses efforts to produce microsensor platforms and Smart Sensor Systems that can be tailored to measure a range of chemical species. This technology development ranges from development of base sensor platforms to the evaluation of more mature systems in relevant environments. Although microsensor systems can have a significant impact on aerospace applications, extensive application testing is necessary for their long-term implementation. The introduction of nanomaterials into microsensor platforms has the potential to significantly enable improved sensor performance, but control of those nanostructures is necessary in order to achieve maximum benefits. Examples will be given of microsensor platform technology, Smart Sensor Systems, application testing, and efforts to integrate and control nanostructures into sensor structures.