This exploratory study examined domain-general cognitive abilities that may serve as aptitudes for interpreting skill by comparing highly skilled signed language interpreters (those considered competent in most interpreting situations) and less skilled signed language interpreters (those considered less than competent in most interpreting situations) on various measures. Specifically, the current study examined the feasibility of predicting interpreter skill level based only on a variety of cognitive abilities and personality traits. We collected data on several cognitive measures, including processing speed, psychomotor speed, cognitive control and task switching ability, fluid intelligence, working memory capacity, and mental flexibility, as well as several personality measures, including risk-taking orientation and emotion-cognition integration style, and intrinsic motivation to engage in complex cognitive tasks. Significant differences emerged between the two groups on both cognitive and personality measures suggesting that a combination of stable domain-general cognitive abilities and personality traits may be responsible for differentiating highly skilled from less skilled interpreters and may therefore be predictive of individuals’ future interpreting effectiveness and skill level.