The Crown is not only Canada's oldest continuing political institution, but also its most pervasive, affecting the operation of Parliament and the legislatures, the executive, the bureaucracy, the courts, and federalism. However, many consider the Crown to be obscure and anachronistic. David E. Smith's The Invisible Crown was one of the first books to study the role of the Crown in Canada, and remains a significant resource for the unique perspective it offers on the Crown's place in politics.

The Invisible Crown traces Canada's distinctive form of federalism, with highly autonomous provinces, to the Crown's influence. Smith concludes that the Crown has greatly affected the development of Canadian politics due to the country's societal, geographic, and economic conditions. Praised by the Globe and Mail's Michael Valpy as "a thoroughly lucid, scholarly explanation of how the Canadian constitutional monarchy works," it is bolstered by a new foreword by the author speaking to recent events involving the Crown and Canadian politics, notably the prorogation of Parliament in 2008.