Today many of programmers use IM to ask others to help then in work problem they are facing, so managers, you will also stop these things...

In fact one can get proper concentration of a programmer by providing him full working conditions. Otherwise IM are not only thing to use. I remember that while I have no work assigned or some internet problem occured at old office, I usually start reading ebooks. So one need to make good policies and adapt good ways instead of just restrictions.

Some good programmers don't join some organizations only due to these reasons.