A dehumidifier for dehumidifying an enclosure is described. The dehumidifier has a desiccant holder for holding a desiccant and a bias mechanism to bias the dehumidifier into a first configuration in which desiccant held by the desiccant holder is exposed to an interior of the enclosure (in order to remove moisture from the enclosure). The dehumidifier also includes a translation means to overcome the bias mechanism such that, when activated, the translation means moves the dehumidifier into a second configuration in which the desiccant is exposed to an atmosphere outside the enclosure (in order to regenerate the desiccant).