Disabling the "cmd" command ?

I was looking for an article that I had read not long ago about disabling the command prompt from users machines. I, as a network administrator, have been having a little trouble from one user who is very adamant about performing file maintenance on the company computer that he has been allowed to use. He fails to see that it is not his equipment to do with as he wants, and the bosses have concerns. He "maintenance" has caused no problems that we have uncovered thus far. I remember the newsletter, but have been unable to find my copy or find it at your website. I have spent enough time on my own looking and am now seeking, I know it is not manly, help finding the article.