The YMCA keeps residents healthy and engaged in more than 10,000 neighborhoods across the country, but it traces its American origins to the streets of 19th-century Boston. Here, Thomas Valentine Sullivan carried on the mission started in London by George Williams: providing affordable recreation and residence to young men from cities and country towns alike. Over the last century and change, the organization's mission changed to keep pace with the evolving times; today, the YMCA of Greater Boston welcomes anyone interested in furthering the causes of "youth development, healthy living, and social responsibility."

This modern mission combines the Y's signature programming with new initiatives designed to keep citizens one step ahead of an ever-changing world. Members stay fit and active with everything from organized sports and fitness classes to lifeguard, CPR, and first aid lessons. But the Y's developmental programs go far beyond bodily strength; their enrichment and leadership courses equip youths with the confidence needed to take charge in their everyday lives, and ESL classes help newcomers to English embark on the next step of their linguistic lives.