The Quad, comprising Australia, Japan, India, and the United States, has evolved from an ad hoc mechanism created during the response to the 2004 Indian Ocean tsunami into a key element of the U.S. Indo-Pacific Strategy. Building on a roundtable workshop organized by NBR that brought together security analysts from each of the Quad countries, this commentary series evaluates the Quad’s recent responses to regional security challenges, identifies opportunities for security cooperation, and explores ways to further develop the Quad.