Civil Engineer

Median pay: $74,700
Top pay: $110,000
10-year job growth: 24%
Total jobs: 170,000

The job: The country's aging infrastructure won't be able to keep up with its growing population without the help of civil engineers. In this field you supervise and design bridges, highways, tunnels, and water and sewage systems. Though the industry has slowed along with the economy, the long-term growth potential is strong, says Kathy Caldwell, president of the American Society of Civil Engineers.

How to switch: This switch will be smoother if you've studied math or physical science. If not, coursework can take around 18 months. A two-year master's degree is recommended, but some jobs don't require it. For a license, you'll have to pass an exam and amass about four years of relevant work experience.