Just the word calculus strikes fear in the mind of many students, but it is a subject that is very valuable to the food scientist or engineer, and one that can be mastered with a little effort. The areas of calculus that will be discussed in this chapter are differentiation and integration, along with their application to real problems in food engineering. The goal here is not to provide the material of a complete calculus text, but to provide the tools one needs to solve engineering problems. Even then, not every tool will be provided. The student should be able to take information here and use it to solve more complex problems. In some instances, one may need to consult another text to perform a difficult step, but the student should have no problem understanding the reference with the nucleus of information presented here.