[Source: http://intjforum.com/showpost.php?p=4557153&postcount=7 ]

I think that overall, I would rather use the Big 5 and parts of the Enneagram over the MBTI for psychotherapy.

Things that would discourage me from using the MBTI:

• possible need to buy rights to utilize it professionally
• potential for confusion toward, or over-intellectualization of the concepts being tested for and examined (esp. if the patient has a problem involving over-analysis of themselves or others)
• the lack of any concept or measure of neuroticism

On the other hand, the MBTI is firmly established within our culture, and is widely recognized as a personality framework/test with decently interesting things to say about people. It also provides a nice language to share with the patient, though I still doubt its usefulness in therapeutic areas outside of, for instance, career coaching or relationship counseling.

The cognitive functions also provide a helpful language, but given the confusion/over-intellectualization point I raised above, I would probably steer clear from them in therapy forms that aren’t at least heavily grounded in cognitive-behavioral traditions. And even then, I would have to strive to simplify and adapt the functions into my own model, rather than emphasize their association with Jung or Myers (since that’s the point where the functions become pure devices of philosophical or academic scrutiny, rather than potentially useful tools for treatment and self-identification per se).

Things that would discourage me from using the Enneagram:

• possible need to buy rights to utilize it professionally
• stigma against its validity and overtly-ethical outlook (the former of which could, beneath the growing specter of evidence-based treatment as the expected norm, lead to a drastic cut in my range of prospective clients)
• general ignorance of the system or what it’s about (also limits my range of patients)
• the need for a longer therapeutic process, since the Enneagram must reach the depths of one’s soul in order to be optimally useful

I would definitely favor the Enneagram over MBTI in psychotherapy, since it gives such a relatively nuanced view of neuroticism. However, I’m a little uncertain of why I would use it over the Big 5, particularly when it comes to formalized assessment: it’s remarkably easy to measure neuroticism’s facets with a short Big 5-adapted survey, but the Enneagram would require building one from scratch (fun, but not entirely practical for most).

I would shift emphasis away from the Enneagram’s type aspect, and focus more on what type’s neurotic patterns a given patient exhibits. I might also use it as a rough way to gauge how healthy (healthy, average, unhealthy) or self-actualizing a person currently is. (The self-actualization component is actually a very viable edge the Enneagram has over MBTI and the Big 5, though I understand one of the key points of MBTI within therapy would be to ‘grow [more successfully] into’ one’s type. In contrast, the Enneagram is all about transcending one’s type, unrealistic though that might be to treat as the goal to reach by the end of each patient’s therapy.)

Finally, regarding the Big 5, I can’t think of much that would keep me from utilizing it. It’s the most conceptually specific (with its facet divisions of each basic personality domain), it provides ready-to-use, non-commercialized assessment tools, and it gives a helpful amount of detail about one’s psyche at the facets level. It also has a neuroticism component that captures the more common problems encountered in psychology, including anxiety and depression, and would be best (in those respects) for gaining an initial understanding of a patient’s maladies. I think the fact that it can’t give you a ‘type’ of person, only a picture of the individual in relation to the norm of people, isn’t really a downside at all: this actually circumvents the potential problem of a patient trying to shoehorn themselves into an idealized form of their type, even if it does detract a bit from their ability to find ‘like-minded individuals’ (they wouldn’t exactly be able to find an rLoAI online forum, for instance).

In the end, I would probably opt to borrow from all three personality frameworks discussed–MBTI to help elucidate cognitive style, Enneagram to identify the basic ‘type’ of a person in terms of potentials for growth/disintegration, and Big 5 to zero in on the specific personality factors worth working with–and adapt their concepts to be suitable both commercially and for my target client base. My therapeutic methodology, of course, would flex in accordance with the needs of each new patient (per the eminent existential psychotherapist Irvin Yalom’s recommendation), and would not rigidly rely on one framework over the others across all cases.