An infrastructure that leverages established wireless messaging paradigms (such as, possibly inter alia, Short Message Service, Multimedia Message Service, Wireless Application Protocol, IP Multimedia Subsystem, etc.) to provide, in new and creative ways, an enhanced level of security for the payment element or portion of a transaction--for example, a transaction within Mobile Commerce (M-Commerce, which, broadly speaking, encompasses the buying and selling of merchant-supplied products, goods, and services through wireless devices), a purchase in the checkout lane of a brick-and-mortar store, a purchase at a (fast-food or other) restaurant, etc. The infrastructure may optionally leverage the capabilities of a centrally-located Messaging Inter-Carrier Vendor.