I believe that healing occurs on more than one plane, or level. The first and most obvious of these is, of course, the physical; if we have pain or other symptoms of disease (think: dis-ease!), these will capture our immediate attention. That said, however, we often find that "healing" must occur across several strata.
The notion of psychosomatic components to illness is certainly not new. Indeed, they were apparently noted centuries ago. Hypnotists, in particular, draw attention to the power of words. If we say that something gives us "a pain in the neck," we may find ourselves suffering from neck and shoulder pains; if we "can't stomach" a situation (job, person, etc.), we may encounter constipation, diarrhea, or ulcers. Of course, many of the connections -- e.g., those involving general stress -- are far more complex. However, in addressing physical symptoms, we must seek a better understanding of the entire problem.
By the 8th century (and probably much earlier), Buddhists and Hindus had become aware of the existence of chakras -- vital energy points within the body. When energy does not flow smoothly through these chakras, physical and emotional symptoms arise. Thus, on a more subtle level, healing may involve the chakras as well.
Finally -- and I always use this word cautiously -- we must reflect on spiritual healing. This has nothing whatsoever to do with Bible-thumping or organized religion. Instead, it deals with the part of us that transcends the body and the intellect; that which is in some ways greater than ourselves and may in fact address the reason we are alive. While a forum of this sort is not suitable for lengthy discussion of this topic, we should at least be open to the possibility that the spiritual plane may also be involved in the healing process.
I shall recapitulate through example: If a client has pains in the upper back, shoulders, and neck, these may arise solely from the physical load he/she is carrying, and thus be treated most successfully on the physical plane (e.g., through trigger-point massage). If family, relationship, and/or work pressures leave the client with the sensation of holding the world on his/her shoulders (like the mythological Atlas), we shall find it beneficial to discuss these feelings and develop coping strategies, as the psychological pressures undoubtedly exacerbate the pains. We may also find related chakric problems -- e.g., a recent breakup (heart chakra); inability to speak about or articulate one's problems (throat chakra) -- and these might also affect certain parts of the body adversely. Then we might see that some of the problem involves an inability to let go (e.g., of anger, disappointment, frustration, or even the pain itself) or forgive (another or oneself), and this may require learning to transcend (as in "transcend the ego"), which is where spiritual growth enters the picture. Some clients may respond wonderfully to treatment on a single plane, but others may require two-, three-, or even four-level healing.