A trailer for launching a boat and a personal watercraft includes a chassis. An elevated platform attached to the chassis supports a personal watercraft above the chassis. A boom assembly pivots relative to the chassis between stored and launch positions. The boom assembly also has an intermediate position above the watercraft. A boom winch controls pivoting of the boom assembly. A watercraft winch on the boom assembly has a cable extending to the watercraft. When the boom assembly is in its intermediate position, the watercraft winch raises the watercraft off the elevated platform. Then the boom winch pivots the boom assembly to the launch position in which the watercraft is in the water. The cables then are released from the watercraft. Thereafter the boat is launched conventionally from the trailer.