A key problem in mobile and ubiquitous computing is that of setting up an association between a pair of devices so that they may communicate securely over a wireless network. It is particularly important to be able to solve this problem for spontaneous associations, which must not depend on pre-existing security values such as certificates, and when the only means of identifying the target device is physical. This paper contributes protocols for validating secure spontaneous associations. The protocols complement existing unauthenticated key- exchange protocols and work over widely used wireless technologies. They improve on previous work by eliminating specialised hardware. We present the protocols and discuss their advantages and limitations. Notes: Seung Hyun Im, Dept of Software and Information Systems, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223, USA 9 Pages