This invention relates to an active agent delivery device. More particularly, the invention relates to a delivery device that includes a sleeve to protect the delivery device from transient mechanical forces. The delivery device of the invention is robust and resistant to transient mechanical forces. The invention provides a fluid-imbibing delivery device comprising a housing enclosing an internal compartment, said housing having a first wall section that substantially restricts the passage of fluid into the delivery device, i.e. is substantially fluidimpermeable, and that contains a beneficial agent; a second wall section that permits the passage of fluid into the delivery device, i.e. is fluid-permeable, and that contains at least one expandable driving member; and exit means; with a protective sleeve means extending from the first wall section of the housing to cover and protect the second wall section of the housing and the junction of the first and second sections. The protective sleeve is preferably configured to provide substantially no resistance to flow of fluid vapor through the fluid-permeable second wall section.