Surface traits are a concept developed by Raymond Cattell whose work concentrated on personality traits. He theorized that there are 16 source traits that are the building blocks of personality. All these traits form part of an individual's personality. When you put the source traits together along with other variables in the environment they make up the surface traits, which are the traits we see and think of as personality. Surface traits are considered one construct of multiple traits that go together.
For example, being altruistic would be a surface trait while source traits that comprise this would be being unselfishness, not greedy, sharing, and being thoughtful. A surface trait is comprised of the source traits that can be observed in an individual and are easily observable and common clusters of behavior. Cattell considered source traits to be more influential than surface traits in studying personality.