Our mission is to provide children facing adversity with strong and enduring, professionally supported one-to-one relationships that change lives for the better, forever. Big Brothers Big Sisters of Greater Manchester was established in 1966 as a full affiliate of Big Brothers Big Sisters of America. In 2004, Big Brothers Big Sisters of America celebrated its 100th Anniversary, making the One-to-One mentoring programs of this organization the best established and most documented for successful results.