The present invention generally relates to systems and methods for delivering and/or receiving a substance or substances such as blood from subjects. In one aspect, the present invention is directed to devices and methods for receiving or extracting blood from a subject, e.g., from the skin and/or from beneath the skin, using devices containing a substance transfer component (for example, one or more needles or microneedles) and a reduced pressure or vacuum chamber having an internal pressure less than atmospheric pressure prior to receiving blood. In some embodiments, the device may contain a “snap dome” or other deformable structure, which may be used, at least in part, to urge or move needles or other suitable substance transfer components into the skin of a subject. In some cases, for example, the device may contain a flexible concave member and a needle mechanically coupled to the flexible concave member such that the needle may be urged or moved into the skin using the flexible concave member. Other aspects of the present invention are directed at other devices for receiving blood (or other bodily fluids, e.g., interstitial fluid), kits involving such devices, methods of making such devices, methods of using such devices, and the like.
