In this talk we discuss some mathematical and computational problems that arise in the design and control of fluid and thermal fluid systems. We present some applications that have not received wide attention in the PDE control community, provide examples to highlight some technical issues and then focus on a special class thermal fluid systems that occur in aircraft environmental control systems. These application areas offer enormous opportunities for researchers interested in distributed parameter control. Finally, we close with some advice for young researchers who might be interested in pursuing these topics.