The District of Columbia has banned the use of cell phones while driving unless they are used in conjunction with head gear.

I try to use them as little as possible while driving, but when a client calls to see if I'm available to work on a given day, I'm taking the call-- otherwise I could be out as much as $400+ while they call someone else. So I take the call. I usually either pull over to talk or ask them if I can call them back shortly.