A device for controlled delivery of an active ingredient to a receiving site (1) such as a plant, human or animal. The device comprises a filmic substrate including a water soluble carrier layer (2) disposed between first and second water soluble control layers (3, 4). The second control layer (4) of the filmic substrate is provided with adhesive (5) on the side remote from the carrier layer (2) for attaching the device to the receiving site (1) with the first control layer (3) outermost. The first and second control layers (3, 4) having perforated regions (9, 8) whereby the carrier layer (2) can be dissolved by wetting the first control layer (3) with an aqueous medium that passes through the perforations (9) of the first control layer (3) releasing the active ingredient into solution that passes through the perforations (8) of the second layer (4) to come into contact with the receiving site (1).