rationale. is a side project consisting of Chicago based pop punk bands Real Friends and Knuckle Puck. The three-man project includes Real Friends' Dan Lambton and Knuckle Puck’s Joe Taylor and Ryan Rumchaks.

This is what the band said on their Bandcamp:

We started rationale. because we love hanging out and making music with our friends. This is what has come of that so far.

Joe, Dan, and their respective bands have always shared a close friendship and have toured together as well.