There still remain some uncertainties about cognitive radio (CR) that slow down the implementation of CR technologies. The obscurity of the required regulatory actions prior to CR adoption is one of the reasons why the industry is still hesitant in moving forward. Vice versa, regulators are waiting for industry to bring forward relevant (business) scenarios in which CR could be used. This way, appropriate regulatory measures can be taken for each of these scenarios. In order to break this deadlock, this paper proposes a classification of distinct scenarios in which CR would be of use, based on three theoretic business parameters. For the resulting scenarios, this paper will identify the roadblocks that hamper CR implementation and this makes it possible to indicate matching regulatory actions that could solve the issues. As will become clear from this paper, distinct scenarios require distinct regulatory measures, of distinct nature (technical, administrative, support, research), taken by regulatory instances on various levels (e.g. national administrations, international administrations, standardization bodies).