Motor shield

I am looking into getting this:
http://www.ladyada.net/make/mshield/index.html

and building it. My question is, it seems like it plugs into all the pins, so how does one have pins left over to add other sensors if one wanted to say build a robot that was driven by motors by this shield and then uses sensors to navigate.

Thanks, I am new to this stuff...

-Shane

The 6 analog pins (or digital pins 14-19) are available on the header at the bottom right of the board (marked A0-5).

digital pins 2-12 are used by the various board functions