Concepts of critical thinking and psychological type are reviewed. An instrument that has gained wide acceptance for evaluating individual preferences is the Myers-Briggs Type Indicator (MBTI). Four dimensions of the MBTI that can also be considered learning preferences, with their associated contrasting preferences, are: (1) orientation toward information and idea generation (extraversion and introversion); (2) perception of information or ideas (sensing or intuition); (3) judgment or decision making (thinking and feeling); and (4) orientation to environment (judgment and perception). Combinations result in 16 type possibilities. Research has established that specific preferences and characteristics are associated with these types. For example,"introvert-sensing-thinking-judgment" learners tend to be analytical, fact-minded, dependable, reflective, and practical. The key to developing a learner's ability to think critically is found in the order of the learner's preferences for perception and judgment. Teaching may be improved by emphasizing learners' dominant ways of perceiving and judging. Learners who know their own preferred and non-preferred approaches can reinforce their strengths while working to overcome their weaknesses. Two tables and two figures illustrate the text. (SLD)