On a cool, grey April morning on Chicago's South Side, Rami Nashashibi walked purposefully into the conference room of the Inner-City Muslim Action Network (Iman) and sat at the head of a rectangular table, where four of his charges awaited instruction.

"I can't explain how much you have on your shoulders," Nashashibi, wearing loose-fitting jeans, a knitted skullcap and a comfortable sweater, told his men. "What we have right now is a little seed, and if we want that seed to become a great forest, we've got to cultivate it."

Nashashibi has been cultivating Iman for nearly 15 years. Today the organisation provides just about everything to those in need in Chicago Lawn, a predominantly African-American neighbourhood with a mix of Latinos and Palestinians. Its free clinic serves the sick from across the city. A computer lab offers technical training. Tens of thousands of people go to its annual concert benefit, Takin' It to the Streets, while its bimonthly music and arts gatherings are well attended. One project supports healthier eating alternatives for the area; another reduces gang violence. A new initiative, Green Reentry, builds eco-friendly houses for Muslims recently released from prison.

Iman's work has earned plaudits for its leader. In 2007, Islamica magazine placed Nashashibi among the 10 Young Muslim Visionaries Shaping Islam in America. The next year he was named one of the world's 500 most influential Muslims by Georgetown University and described as "the most impressive young Muslim of my generation" by Eboo Patel, chairman of President Barack Obama's interfaith task force. Last autumn, the US state department sent Nashashibi on a diplomatic speaking tour of Afghanistan and Saudi Arabia.

Earlier this year, Iman received another honour: Imam Habib Umar, the director of Dar Al Mustafa, based in Yemen's Hadhramaut Valley, and among the world's top institutions of Islamic education, spent an afternoon in Chicago Lawn as part of his first North American tour. He visited the organisation's Transitional House, where Muslim men recently released from prison stay until they can get on their feet, and delivered a speech on spirituality and community accountability. "The most beloved of God's creatures are those who are most beneficial to others," Umar had said, thanking Iman members for "fulfilling a communal obligation upon all Muslims".

Nashashibi balances a commitment to Islam, an intellectual rigour and an unstinting morality with the style and mannerisms of the street. He has a PhD in sociology from the University of Chicago, where he teaches, and has worked in high-security prisons and some of the city's roughest neighbourhoods. On the South Side, he is friendly with shopkeepers, businesspeople and political and religious leaders and trusted enough by school administrators to be called in to mediate student disputes.

"We must serve humanity by serving the creator in the most humble way possible," Nashashibi advises the men in the conference room. "What we do on all levels continues to represent the larger project. You're being watched now by Habib Umar. People around the city, around the country, around the world, are hearing about our work."

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