The U.S. job market is constantly evolving and changing. Many jobs that once ranked among the most desirable are now less desirable, while many of the best jobs have only existed for a few years.

While employees’ job satisfaction can largely depend on their particular employer, certain career fields tend to report higher salaries, better working environments, and lower levels of stress than the average American occupation, leading to higher job satisfaction.

24/7 Wall St. reviewed the 2018 Jobs Rated Report from CareerCast, a targeted job opportunity website, to determine the best jobs in America. This report ranks over 200 careers on the overall quality of their work environment, amount of stress, occupational outlook, and income.

Salary is, of course, an important factor in job satisfaction, but many other factors can affect the overall quality of a job. A high amount of stress in the workplace, for example, can erode job satisfaction — even for those working in one of the highest paying jobs in the country.

The overall health of an industry can also be a factor. Those working in rapidly growing industries may be excited about their room for advancement and future career prospects, while those in fields with little job security are often concerned layoffs may be around the corner.

Many of the jobs with the highest job satisfaction ratings are concentrated in the STEM fields — science, technology, engineering, and mathematics. Software developers, doctors and medical workers, and mathematicians largely report good work environments, high compensation, and relatively little stress.

To determine the best jobs in America, 24/7 Wall St. reviewed the 2018 Jobs Rated Report from jobs website CareerCast. We supplemented the CareerCast ranking with data from the U.S. Bureau of Labor Statistics. Data on median annual wages and total employment came from the BLS Occupational Employment Statistics program. Projected job growth rates also came from the BLS.

Click here to see the 25 best jobs in America.