Software for transportation systems is mostly considered to be safety critical, which is good news for all of us who ride upon them! In most respects, the development of a safety critical application for transportation does not differ from one utilized in another context. For safety critical applications, C is often the only available programming language. Even though it has its challenges, with care C may be used to produce safe, reliable, portable and maintainable code. Following the MISRA C guidelines helps achieve these goals.