Personality traits are stable predictors of things like income and happiness, but they can also change with effort and experience, researchers say.

To perceive self-driving cars as safe, they have to have certain personality traits, researchers say. Here are the ones that matter most.

How much do the behaviors of obesity and addiction overlap? A look at personality research finds some connection, but it's complicated.

A new book digs into the psychology of thrill seekers to find out why they thrive on fear. Take the quiz to see how adventurous you are.

New research on arrogance provides a spectrum for the condition with three different levels.

A new study that followed first-year college students until they were in their 40s shows that narcissism tends to decline as we age.

Personality traits like risk aversion and patience might be less who you are and more where you are, research with kids in four countries suggests.

People with greater optimism are more likely to live longer and to achieve "exceptional longevity"—that is, getting to age 85 or older.

In the same way time and big events can change people's personalities, dog personalities can change over time, too.

For happiness in love, don't focus on compatibility. Instead, aim to find someone nice.