Cylindrical polycation brushes form an ionic complex with surfactant sodium dodecyl. sulfate (SDS) in aqueous solution, which causes a worm-to-sphere collapse of the brush. alpha- and beta-Cyclodextrin (CD) returns the brush to the worm-like conformation by forming a supramolecular inclusion complex with SDS. When beta-CD was employed for the inclusion complex, addition of 1-adamantylammonium chloride releases SDS by forming a stronger inclusion complex, causing the recollapse of the brush to spheres.