A vesicle-micelle transition and intermediate structures in ABA and rake-type siloxane surfactants are reported. At low surfactant concentrations, systems show vesicles of various sizes coexisting with spheroidal micelles and elongated micelles about 80 angstrom in diameter. In some instances wormlike micelles are seen in the system with vesicles. Intermediate structures such as open vesicles and pieces of lamellae are also observed. These suggest that when the vesicle-to-micelle transition takes place, the vesicle first opens and then breaks into fragments of lamellae, which finally transform into either spheroidal or wormlike micelles. Toroidal vesicles are also reported.