I chanced upon an article on Inner Peace in my StumbleUpon travels, and was caught by this concept. My recent deeply anxious state was pretty well the opposite of inner calm.
Now I awlays blame the intensity and my hair trigger nature of my emotional response to the World as an underlying weakness and cause of some many problems.
For example, excessive emotions to females when young pushed them out of reach. I react to injustices with excessive anger, even if not expressed. Anxiety before playing in a tennis tournament severely limiting my ability. And so on.
Now I have always felt that my emotional signature was fairly will immutable. Indeed, it might well be.
But I have bought a few books that might help. Essentially, they are centred around the taming of the Ego.
The Ego, it seems, employs emotion to reinforce its behaviours and carry out its wishes.
The more you can calm it down, so that it is more rational, and less devisive, the calmer you are, and the more you will enjoy life.
It is certainly worth a try.