Troubleshooting sticky drawers

[Alan Kalker]

297814

The nightstand above has a sticky middle drawer. But I can't figure out where it is sticking. Is there any systematic way that you use to figure out where the problem is?
Thanks
Alan

[Brian Hale]

I'd rub chalk on the sides and see where it comes off as you open and close it

[Justin Ludwig]

What Brian said. I'd take the top and bottom drawers out too, so I could look inside while operating the drawer. Double check it for square to make sure it isn't racked.

[Al Launier]

Second the above!