The third installment of SPEXcast's "Mars May" leads us to a part of interplanetary missions that doesn't get much attention. We often discuss the capabilities of rovers, their designs and objectives, and all the science learned from years spent on the surface of Mars. But what about the engineers who interact with the rovers themselves? What goes into operating a vehicle millions of miles away, and what is a typical work day like? To answer these questions, we spoke with Doug Klein, a sampling systems engineer who spent the last few years working with Curiosity's Mars Science Lab (MSL) and is now a Robotic Arm Flight System Engineer for its successor, the Mars 2020 rover. Doug has experience with daily downlink analysis for sample acquisition and processing, planning out the rover's actions on the uplink side of things, and investigating anomalies and their contingency plans when things went wrong. You can check out additional links and references at https://blog.spexcast.com/mars-rover-operations-doug-klein .