Fortunately, or unfortunately, depending on how you look at it - we're not at the school age. Nou, who is now 20 months, is *always* home with me

We make it work, I have gotten pretty good at getting tons of work done in the a.m. when she is having breakfast and during naptime.
Like Jen, I will let a client know ahead of time if I have Nou around during a call - most of the time my husband is able to distract her in another room for just long enough though.