Somewhat like Freud's psychoanalysis, MBSR can help people improve their life experience from frank suffering to being able to function better. Freud called this humble therapeutic goal "ordinary unhappiness" - less than ideal, but far better than incapacitating neurosis.
Some Dharma teachers, like Titmuss below, criticize MBSR for being "watered-down" (eviscerated?) Dharma. From my perspective, MBSR is an excellent entry point, even for the very few who may wish to go much deeper after their immediate suffering has abated. MBSR training can serve as an entry point, not necessarily only into a deeper engagement with Buddhism, but any religious or philosophical tradition. Suffering is what tends to bring people to not just to MBSR, but to Zen, other major religions, psychiatry & psychology as well. And after one of these has provided some relief from acute suffering, very few commit to the entire journey. Their particular life stage is filled with other priorities. Most people are not ready to undergo a radical transformation of heart-mind-body. "It is easier for a camel to pass through the eye of a needle ..."
“It is not unusual for profound teachings to get watered down to popularize them. There are a few sins in teaching the Dharma and one of them must surely be reducing the teachings to the overcoming of stress. A life dedicated to the Dharma embraces more than meditation and mindful exercises for coping calmly with daily life. … calmness and clarity of mind … can never serve as a substitute for liberation.
In essence, liberation is the realization of the end of suffering, the full emancipation of the human spirit and the joyful understanding of the nature of things. Cessation of suffering removes the struggle born of greed, hate and self-delusion. It eradicates that compelling need to pursue or gain things as an ultimately satisfying way of life. The emptiness of the ego, of any substance to I and my, is obvious.”
Christopher Titmuss. "Light on Enlightenment. Revolutionary Teachings on the Inner Life." Shambhala, Boston, 1999.