In the early 21st century, societies and their governments around the world have been meeting unprecedented challenges, many of which surpass the capacities, capabilities, and reaches of their traditional institutions and their classical processes of governing. Among these challenges are the need for an accelerated transition of the global economy from its current fossil fuel basis to renewable energies, the so-called post-carbon era also known as the third industrial revolution, the containment and reduction of government spending and debt financing, the increasing rapidity of market changes, and the expanding lag of timely interventions via traditional lawmaking and government action. While upholding the proven principles of Western democracy, democratic self-governance in 21st century market economies apparently needs to develop new institutional formats and novel mechanisms for staying abreast with the systemic dynamics of a tightly interconnected global society. We claim that actionable and omnipresent information along with its underlying technologies are substantial prerequisites and backbones for developing models of smart (democratic) governance, which foster smart, open, and agile governmental institutions as well as stakeholder participation and collaboration on all levels and in all branches of the governing process. We present and discuss an agenda for research and practice, which advances the concept of smart, open, and participatory government of the 21st century.