A multi-purpose tow bar for a trailer and a trailer having a multi-purpose tow bar. In a towing position the tow bar couples the trailer to a moving vehicle such as a bicycle. In a stabilizing position the tow bar supports a stabilizing wheel extending forwardly of the trailer frame, converting the trailer into a self-supporting vehicle such as a stroller or jogger. The tow bar is reversible, comprising first and second end portions which in the preferred embodiment respectively extend from one another at an angle.