What they do all day? It's all about getting oil and gas out of the ground -- and the more, the faster, the better. Reservoir engineers run computer models and perform specialized calculations to try to figure out how much oil or gas is below the surface, how much of it can be retrieved, and the best way to get it.

How to get the job? A degree or background in petroleum or chemical engineering is typical, although there's also room for geologists to adapt their skills to the field. Most big companies require a few years of field experience in drilling or production, and may provide additional industry training.

What's great? What's not? Engineers work with the latest technology and highly skilled, intelligent people. They also get to work outdoors in the field at times. But there are a lot of hours spent staring at a computer screen, and it can be frustrating to devote so much energy to making educated guesses. --K.A.

What they do all day? It's all about getting oil and gas out of the ground -- and the more, the faster, the better. Reservoir engineers run computer models and perform specialized calculations to try to figure out how much oil or gas is below the surface, how much of it can be retrieved, and the best way to get it. --K.A.