The Myers-Briggs personality type ISTJ, short for introversion, sensing, thinking and judgment, is often described as calm, cautious, stable and conventional. These people are logical, organized and serious traditionalists capable of making tough, responsible choices. ISTJs are thought to be the most common personality type at an estimated 16 percent and are about twice as likely to be male as female. They are slightly more common in the African-American population.
A typical ISTJ is a bank officer, financial manager or small-business owner. He likes head-down, detail-oriented work such as accounting in which the rules are clear and straightforward. Law enforcement also draws this personality type. On the negative side, the ISTJ is also more likely to experience chronic pain, cardiac issues or hypertension.
Because they are conscientious and hard workers, the ISTJ person generally maintains a relatively high college GPA. They like to be safe and secure and are particularly interested in financial security. They are introverts, so small talk and meaningless socializing does not interest them. Instead, they prefer useful tasks. At parties, the ISTJ person is more likely to be helping refill the snack table or hang up coats than circulating the room. ISTJs are often thought to be cold or to lack personality. This is not true; the ISTJ simply keeps emotions inside, displaying a calm exterior to the world.