Can mind be controlled?

"Can mind be controlled" ? This question is troubling me for last few days. Have been reading few self development books since past few years. Many of them talk about changing life by changing thinking pattern. This needs controlling your mind and creating thought habits that change your life. I have been wondering if it is really possible.Authors of those books claim it is. They say you need practice to do it. I am not convinced. Has any one done it successfully ? I would like to meet one such person. Get in touch with me if you are one such person and share your experience.