Mission Matters sheds a fresh light on how to envision relevant and impactful museums. Anderson takes the understanding of mission relevance to a new level. The premise of the book makes direct links to external contemporary realities and the need for museums to better position themselves as leaders and change agents in the greater landscape and diversity of people of our times. Anderson illustrates her points with numerous examples from here in the United States and from around the world. Features include thought essays by David Fleming from the UK who tackles the importance of mission and social issues, and Charmaine Jefferson who frames the complexities of cultural competence in the 21st century. Twenty museum leaders each share their institution’s story of transformative change tied to reframing their mission. Anderson’s central tool for the book, the Mission Alignment Framework, helps reference the thinking about missions and the subsequent changes within museums as they redirect their work. Eighty US and international mission statements reveal the range of museums from urban and rural to different types of museums, styles of mission all illustrating relevance in a way unique to their location, institutional capacity, resources, and purpose. Complementing these examples are: guidelines about how to rethink mission; a questioning strategy based on the Mission Alignment Framework; and, a range of useful tools from museums and leading thinkers in the field. Mission Matters is useful to a wide range of readers and users from trustees to directors to staff from a wide range of museums regardless of size and stage of development and maturity. The book is an easily accessible reference for strategic planning, conversations about relevance and missions, and museums considering the reinvention of their museum for greater impact.