The job market’s most sought-after skills can be tough to spot on a résumé.

Companies across the U.S. say it is becoming increasingly difficult to find applicants who can communicate clearly, take initiative, problem-solve and get along with co-workers.

Those traits, often called soft skills, can make the difference between a standout employee and one who just gets by.

While such skills have always appealed to employers, decades-long shifts in the economy have made them especially crucial now. Companies have automated or outsourced many routine tasks, and the jobs that remain often require workers to take on broader responsibilities that demand critical thinking, empathy or other abilities that computers can’t easily simulate.

As the labor market tightens, competition has heated up for workers with the right mix of soft skills, which vary by industry and across the pay spectrum—from making small talk with a customer at the checkout counter, to coordinating a project across several departments on a tight deadline.