The conference room was packed with members of the compound development team. I was the new scientist in the group, having recently made the move from a medical school faculty to the biochemical division of a major pharmaceutical company, and I was still trying to get my bearings. Surrounding me were scientists from departments of chemistry, pharmaceutics, pharmacology, drug development and metabolism, and biology. Even marketing, regulatory affairs, and a department called quality assessment had representatives assigned to the team. Collectively, we were charged with selecting the most promising compound from a yearlong screening effort, proposing additional experiments, and collecting the necessary supporting data to propose it as a new drug candidate to senior management.

As I sat through the first of what were to be many weekly team meetings, I reflected on how different the corporate world was from the university environment to which I had become accustomed. As an academic with tenure, I worked with great autonomy. As long as grant money flowed into my small laboratory, I could pursue any line of research that struck my fancy, and I could proceed at my own pace and follow my own proclivity. Sure, I sometimes worked as a member of a team, usually with postdocs or graduate students, but I was the senior person. There was a clear-cut pecking order, and if I chose, I could have my way in making critical decisions. This was different; here we were peers with different areas of expertise. We had to make decisions and act through consensus.

In addition, there were great differences in temperament among the members of the team. Some would have been delighted to spend the afternoon trudging through the details of spreadsheet after spreadsheet of experimental detail. Others seemed immersed in the minutiae of the assay methodology, without any apparent appreciation or understanding of the overall biological pathway that the chemical compounds were designed to perturb - the theoretical underpinning of the project, to my mind. Some team members seemed to devote inordinate attention to comparing every result to data from previous projects, while another group tuned out the details of the assay or past data and focused on the remotest possibilities for utilization or chemical modification of the compounds and the most arcane connections to other successful drugs. Some members sat quietly taking in the presentations that afternoon, while others were vocal, expanding upon or challenging the material presented.

Participating on this team was going to be a totally different and demanding experience, and I felt very uncomfortable. My response was to retreat into my favored role as a quiet, analytical observer. As the afternoon wore on, I behaved as if I had climbed into an imaginary submarine, executed an emergency dive, and was observing the proceedings through the safety of a periscope, as I quietly mulled it all over in my mind.

As time progressed, I became more comfortable with my new team environment and at times even reveled in interacting with such a diverse group. It was not until later, however, while taking company-sponsored management training courses, that I really began to understand and appreciate the team dynamic. Although initially I had been taken aback by the diversity of personal styles on the team, I discovered that the interaction of individuals with different styles and temperaments, as well as different professional expertise, is what provides synergy. That is, it's what makes the overall ability of the team much greater than just the sum of the abilities of the individual members.

"Each of us has a preferred temperament that seems to be 'hardwired' and can be identified in early childhood," says Susan Nash, a training specialist, consultant, and author of Turning Team Performance Inside Out: Team Types and Temperament for High-Impact Results. In this book, Nash describes the four basic temperaments - Artisan, Guardian, Rational, and Idealist - which were first delineated by David West Keirsey, a behavioral scientist who developed the modern theory of temperament in 1956 in his book Please Understand Me: Character & Temperament Types.

Each of the four temperaments has distinct strengths and potential weaknesses. "The power of the team dynamic is in the combination of the strengths of all four temperaments," says Nash. It allows the team to approach a problem with many more perspectives than are possessed by any one individual, and it compensates for the potential weakness of any one person's approach. Of course, this dynamic depends on the team's actually being composed of people with different temperaments. If a team leader does not understand the importance of a variety of temperaments and selects only members with temperaments like his own, team interactions will likely be more comfortable, but much less productive.

The concept of temperament is based on an understanding of psychological types first identified by psychologist Carl G. Jung in the early 1900s. "This work sprang originally from my need to define the ways in which my outlook differed from Freud's and Adler's. In attempting to answer this question, I came across the problem of types; for it is one's psychological type which from the outset determines and limits a person's judgment," wrote Jung in his Memories, Dreams, Reflections. His book Psychologische typen was published in 1921; an English translation, subtitled "The Psychology of Individuation," appeared in 1923.

Jung's theory was elaborated upon and made accessible to the general public in the United States by the mother-daughter team Katharine C. Briggs and Isabel Briggs Myers. Today the Myers-Briggs Type Indicator (MBTI) instrument, a 94-item questionnaire of preferences, is used to identify quickly a person's psychological type, which can then be related to temperament. The MBTI is designed to identify the preference for four pairs of Jungian functions, which reflect preferred ways of relating to the world, collecting information, and making decisions. Each of the four functions has two possibilities, giving a total of 16 distinct psychological types.

The best known of the Jungian functions is the pair termed Introversion (I) and Extroversion (E). If a person prefers to focus on the world outside the self, or is energized when interacting with other people, then the term Extroversion would apply. If an individual prefers to focus on an inner world or gains energy by tuning in to her inner dialogue, the opposite, Introversion, applies. Frequently the extroverted individual will spend nonwork time in activities that involve interacting with other people; the introvert, on the other hand, will recharge her batteries in more solitary pursuits and may require down-time alone in order to feel refreshed and rejuvenated.

The functions that describe how we gather information are termed Sensing (S) and Intuiting (N). A person who prefers to gather information using the various senses is considered a Sensing type, while a person who prefers to use intuition is termed Intuitive. The Sensing person tends to look for a concrete basis for information. The Intuitive person tends to focus more on finding meaning and on possibilities and relationships, types of information for which it is more difficult to provide hard evidence.

The different ways of arriving at decisions are termed Thinking (T) and Feeling (F). Thinking involves relying on what logic tells us regardless of whether or not we like the decision, while Feeling is more subjective and often involves values and personal preferences.

The last two functions are termed Judging (J) and Perceiving (P); they describe how one prefers to relate to the external world. A person with a Judging function would prefer to have closure; she wants to bring things to a head and make a decision or take an action. The Perceiving individual, on the other hand, tends to be more flexible and open-ended. He always sees additional options to explore before coming to a conclusion or making a decision.

My initial impression of the MBTI was that it had to be grossly oversimplified and was therefore of little use. However, I was already enrolled in a class called "Understanding You" in which I was to complete the MBTI to determine my own psychological type and temperament, so I went ahead with it. My type turned out to be INTJ, which correlates with the rational temperament. I remained skeptical until I read the descriptors of the INTJ psychological type and the rational temperament. I was blown away - it was a dead-on-accurate description of me - which turns out to be not an unusual reaction of first-time users of the MBTI.

Just because the MBTI indicates that a person is a certain type, it doesn't mean that he cannot act like a different type. It just means that another type is not that person's preferred mode of action, and to act otherwise requires extra effort. I certainly can and do frequently behave like an extrovert by relating to other people and "getting out of my head," but sometimes it does exhaust me. Rarely do I gain energy by acting like an extrovert, and I would almost always rather spend a quiet evening at home reading or visiting with friends than going out to a social event.

One major use I found for this insight about myself is in arranging my work schedule in a way that makes me most productive. I'm a professor at New York University, where I once lectured four days a week. After explaining to the head of my program the enormous toll on my INTJ psyche it took to meet classes four days a week, I successfully negotiated the same number of lectures on a two-day-a-week schedule. Now I expend the energy to be "on" for lectures only twice a week (which usually exhausts me on those days) and spend the other three days engaged in more solitary, INTJ-like pursuits such as reading, writing, and thinking.

As for the work team, it turns out that crawling into my imaginary submarine, submerging, and becoming the quiet, analytical thinker was totally predictable for my type and temperament. It did not mean that I was less involved or less valuable than the more vocal members of the team, only that I had a different way of looking at the problem, utilizing my own distinctive analytical style. On the other hand, the group would not have benefited if the room had been filled with INTJs. Clearly, to create the most effective team it was necessary to have members with a diversity of types and temperaments. As the Talmud says, "We do not see things as they are, we see them as we are. We do not hear things as they are, we hear them as we are."