While there are many useful ways of describing and discussing the Digital Era, explanations of its existence are lacking. The Digital Era is characterized by technology which increases the speed and breadth of knowledge turnover within the economy and society. Evolutionary theory, as an explanation of the system we live in, states that sustainability relies on knowledge turnover. In parts of the system which are relatively stable, knowledge turnover is low, and new variation, when produced, is rarely retained. In other, less stable parts of the system, faster knowledge turnover is advantageous as new knowledge is produced more frequently allowing for adaptation to the changing surrounding environment. Mixing and matching rates of knowledge turnover makes for a dynamic but ever-lasting world. The Digital Era can be seen as the development of an evolutionary system in which knowledge turnover is not only very high, but also increasingly out of the control of humans, making it a time in which our lives become more difficult to manage. For example, in the second generation Internet, ‘the semantic web’, functionality, which understands meaning, replaces the search function of unknowingly matching words, which often have multiple meanings. In time, within this version of the Internet, software agents will exchange knowledge without human intervention. Equally, our understanding of the knowledge embedded within the human genome about how we relate to the world, generated in association with technology and freely available on the Internet, raises questions about our assumptions of control. Do we know enough about our future to change our genome? Can we control such changes and their diffusion? The social and economic implications of the Digital Era are huge and will increase as technological functionality becomes more knowledge-based, our everyday lives and understanding of ourselves become more linked to it, and it takes on a ‘life’ of its own. Understanding the Digital Era in terms of evolution will help ensure we build sustainable socio-economic relationships both with technology and with the advanced knowledge that technology helps us create.