Technological research in cyber security is commonly driven by short-term priorities dictated by evolving threats, technological trends, and funding availability rather than by a long-term and sustainable outlook. For a technical cyber security solution to be sustainable, it needs to exhibit not only performance effectiveness but also cost efficiency, energy efficiency, and compatibility with the existing business processes, regulatory environment, and economic factors, along with consideration of the future landscape, and—of course—user acceptance. In fact, sustainable cyber security solutions likely need people not only to accept them but also to participate actively. This theme will help researchers set targets for innovations that work both now and over the long run by prioritising cost efficiency, multidisciplinary collaboration, and the involvement of the human.