A transdermal drug delivery apparatus comprising: a receptacle comprising a housing (30, 32) and a microneedle assembly mounted to the housing (30, 32); a reservoir for being mounted to the receptacle, the reservoir having an interior for containing fluid for being supplied to the microneedle assembly; characterized in that the apparatus is adapted so that, when the apparatus is assembled, the reservoir is configured to move relative to the microneedle assembly along a path from an outer position to an inner position, the reservoir is closer to the microneedle assembly in the inner position than in the outer position, in the outer position, the reservoir is out of fluid communication with the microneedle assembly, and in the inner position, the reservoir is in fluid communication with the microneedle assembly; and a plurality of connector parts (56, 218, 132, 134, 210) spaced apart from one another along the path, and configured for releasably securing the reservoir in the outer position, and securing the reservoir in the inner position; and by a first force provider configured to provide a first force to force the microneedle assembly outwardly from the housing (30, 32) and against the skin of a user; a second force provider configured to provide a second force to cause at least some of the fluid to flow from the reservoir to the microneedle assembly. a receptacle comprising a housing (30, 32) and a microneedle assembly mounted to the housing (30, 32); a reservoir for being mounted to the receptacle, the reservoir having an interior for containing fluid for being supplied to the microneedle assembly; characterized in that the apparatus is adapted so that, when the apparatus is assembled, the reservoir is configured to move relative to the microneedle assembly along a path from an outer position to an inner position, the reservoir is closer to the microneedle assembly in the inner position than in the outer position, in the outer position, the reservoir is out of fluid communication with the microneedle assembly, and in the inner position, the reservoir is in fluid communication with the microneedle assembly; and the apparatus is adapted so that, when the apparatus is assembled, the reservoir is configured to move relative to the microneedle assembly along a path from an outer position to an inner position, the reservoir is closer to the microneedle assembly in the inner position than in the outer position, in the outer position, the reservoir is out of fluid communication with the microneedle assembly, and in the inner position, the reservoir is in fluid communication with the microneedle assembly; and a plurality of connector parts (56, 218, 132, 134, 210) spaced apart from one another along the path, and configured for releasably securing the reservoir in the outer position, and securing the reservoir in the inner position; and by releasably securing the reservoir in the outer position, and securing the reservoir in the inner position; and by a first force provider configured to provide a first force to force the microneedle assembly outwardly from the housing (30, 32) and against the skin of a user; a second force provider configured to provide a second force to cause at least some of the fluid to flow from the reservoir to the microneedle assembly.