So-called "mindfulness" techniques have been recommended in the treatment of a variety of problems, including chronic physical pain, emotional lability, anxiety, borderline personality symptoms, etc.
I do not think mindfulness training is a complete answer to any of these complex problems, but it could be an extremely valuable, essential component in therapy and growth.
I think now of a metaphor of a growing seedling, or a baby bird: these creatures require stable environments in order to grow. Internal and external environments may not always be stable, though. This instability may be caused by many internal and external biological, environmental, social, or psychological factors. In an unstable environment, growth cannot occur--it gets disrupted, uprooted, or drowned, over and over again, by painful waves of symptoms. Mindfulness techniques can be a way to deal with this type of pain, by taking away from the pain its power to disrupt, uproot, or drown. In itself it may not lead to psychological health, but it may permit a stable ground on which to start growing and building health.
Mindfulness on its own may not always stop pain, but it may lay the groundwork for an environment in which the causes of the pain may finally be dealt with and relieved. In this way mindfulness can be more a catalyst for change than a force of change.
Here is some research evidence:
This is a link to two of Kabat-Zinn's papers: the first describes the results of an 8-week mindfulness meditation course on anxiety symptoms in a cohort of 22 patients, and the second describes a 3-year follow-up on these same patients. The results show persistent, substantial reductions in all anxiety symptoms. The studies are weakened by the lack of placebo groups and randomization. But the initial cohort had quite chronic and severe anxiety symptoms (of average duration 6.8 years). Symptom scores declined by about 50%, which is very significant for chronic anxiety disorder patients, and represent a radical improvement in quality of life.
These papers suggest that mindfulness does not merely "increase acceptance of pain"--they suggest that mindfulness also leads to direct reduction of symptoms.
This is a link to one of Kabat-Zinn's original papers showing substantial symptom improvement and quality-of-life improvement in 90 chronic pain patients who did a 10-week mindfulness meditation course.
This is a 2004 meta-analysis concluding that mindfulness training, for a variety of different syndromes of emotional or physical pain, has an average effect size of about 0.5, which strongly suggests a very significant clinical benefit. It does come from a potentially biased source, "the Freiburg Institute for Mindfulness Research." But the study itself appears to be well put-together.
This randomized, controlled 8 week study showed slight improvements in various symptoms among elderly subjects with chronic low back pain. Pain scores (i.e. quantified measures of subjective pain) did not actually change significantly. And quality of life scores didn't change very much either. So I think the results of this study should not be overstated.
I do think that 8 weeks is too short. Also the degree of "immersion" for a technique like this is likely to be an extremely important factor. I think 8 weeks of 6 hours per day would be much more effective. Or a 1-year study of 1-hour per day. Techniques such as meditation are similar to learning languages or musical skills, and these types of abilities require much more lengthy, immersive practice in order to develop.
In the meantime, I encourage people to inform themselves about mindfulness techniques, and consider reserving some time to develop mindfulness skills.