We knew we needed to integrate her fully in our lives so we trained her to do this.
First we had the boys sit in the box with her. Since she's a *huge* fan of squirrels and we were worried that they'd tempt her too much, we decided to rig a harness system for her so she could ride on her own. We took out the bakfiets' folding front seat, used the hole openings, and screwed two short 'leashes' with clips to either side. We clip these to a body harness and she can sit and move around comfortably but she can't jump out upon squirrel sightings.
So this is how she and P get to work. Yes, besides being a cargo bike dog, she's also an office pup.