The invention provides a transcutaneous
medical device (502, 250, 150, 600) comprising a lower surface adapted for application towards the
skin of a subjet, attaching means (571, 272, 161) for securing the lower surface relative to the
skin, and a transcutaneous device (530, 182, 213, 651) adapted to penetrate the
skin of the subject. The transcutaneous device is mounted for movement be-tween an extended position in which the transcutaneous device projects relative to the lower surface and a retracted position in which the transcutaneous device is retracted relative to the lower surface. The
medical device further comprises release means (550, 275, 162) which can be oper-ated from a first state through an
intermediate state to a second state, whereby operation of the release means from the first to the
intermediate state causes the transcutaneous device to be moved from the extended position to the retracted position, and operation of the re-lease means from the intermediate to the second state causes release of the attaching means.