Cognitive radio has been claimed to be a hopeful solu-tion to the existing conflicts between spectrum demand growth and spectrum underutilization. The basic underlying idea of cognitive radio is to allow unlicensed users to access in an oppor-tunistic and non-interfering manner some licensed bands tempo-rarily unoccupied by licensed users. The cognitive radio concept relies on two basic premises: the current spectrum underutiliza-tion, which has been demonstrated in some spectrum measure-ments campaigns, and the ability of unlicensed users to effectively detect and identify the presence of different licensed technologies in order not to cause harmful interference. In this context, this paper reports the joint work on these two areas that is currently being carried out in the framework of the FP7 Network of Excel-lence in Wireless COMmunications (NEWCOM++). Concretely, this paper presents spectrum occupancy measurements con-ducted in the frequency range from 75 MHz to 7075 MHz that demonstrate the low degree to which spectrum is currently used in an urban outdoor environment and also describes the blind standard recognition sensor concept, a sensor embedded in a cognitive radio equipment to enable the identification of many commercial wireless standards without the need to connect to any network. The joint research in both areas is a key step in promot-ing and validating the idea of dynamic spectrum usage.