The most complex personality classification method is the Myers-Briggs Type Indicator (MBTI). The MBTI model of personality identifies your personality preferences.

It is based on your four preferences (or inclinations) for certain ways of thinking and behaving. There are actually multiple forms of the MBTI for various uses. For more information on the MBTI, and to complete a more detailed assessment for a fee, visit its website at www.myersbriggs.org.