At their summit meeting in Lisbon in November 2010, the heads of state and government of NATO’s 28 member states agreed on a new strategic concept. The document, titled “Active Engagement, Modern Defence”, is meant to both demonstrate and strengthen the political and strategic consensus within the Alliance. It is the first of its kind since 1999, and thus NATO’s first encompassing basic policy document reflecting the experiences of 9/11 and the wars in Afghanistan and Iraq. This analysis presents the strategic concept’s most important elements and comments on their political significance.