For years, my approach to email was like slaying a hydra. For every email I deleted, two more landed in my inbox.

Part of the problem, I knew, was the nature of my work. My team stands between two major organizations within my company, making collaboration crucial, however inefficient it was in practice. So not only did I put up with this mess, I was actually complicit in letting it worsen. I saved everything. I thought most messages addressed directly to me needed my response. I was wrong.

Looking back, I didn’t have the discipline and discernment to really manage my email habits. The system I use now isn’t a product of my own invention. My best friend works for a major consulting firm, and I was grateful when he sketched out the rough strategy his firm shares with consultants to help them manage their own unruly inboxes. The technique comes with all the beauty and simplicity you’d expect from a firm charging seven figures per engagement–and it relies on a folder system you can tally on one hand.

The biggest mistake, in my experience, is creating folders based on topics. Emails, like meetings, rarely stay on track.

My newly streamlined, uncluttered inbox has a grand total of five folders.

Where do you file an important update that covers two unrelated projects? What do you do with that same email if it requires a response?

The second mistake I’ve seen, and personally committed, is trying to use an inbox as a to-do list. There simply aren’t enough hours in the workday to respond to the emails that pile up there. Over time, precisely because of the way I was “organizing” my inbox, emails that I should’ve responded to got pushed further and further down, and were eventually forgotten.

The system that saved my sanity requires only five folders: