Stephen Lewis wears his trade union politics over his heart. Dressed in a crisp blue denim shirt with CUPE monogrammed on the pocket, he sits across the dining room table of his comfortable Forest Hill house on a rainy Saturday. The room is a hybrid: solid Canadian furnishings and eye-grabbing paintings, pottery and sculptures in bold, undulating shapes and colours, from Africa. More than alert, Lewis seems coiled like a Slinky that has boinged into Toronto and is about to boing out again to another speech, another rally, another fundraiser. Last night he slept in his own bed for the first time in weeks—“not bad,” he says, reciting an itinerary that swept through Namibia, New York and Ottawa. He’ll be off again tomorrow. It’s all part of a schedule that has him delivering 200 speeches and travelling some 300,000 kilometres a year—and that’s in addition to the 10 overseas trips he makes annually as the United Nations’ special envoy for HIV/AIDS in Africa.

Lewis speaks with the wallop of a stump preacher and the passion of an old-style unionist. A virtuoso of superheated adjectives, he’s always talked as though there were an editor buried in his larynx, tidying his syntax and thumbing through a thesaurus. Ironies are “acrid,” observations are “heretical” and forces are “malevolent.” What’s different about Lewis the UN envoy, versus Lewis the politician or Lewis the labour arbitrator, is his focus. Battling AIDS in Africa has been his most visceral campaign. It has burnished his messianic fire.

His noisy diplomacy has made him a fundraising and advocacy juggernaut. He’s not the only UN special envoy for HIV/AIDS. But the other three—George Alleyne for the Caribbean, Nafis Sadik for Asia and Lars Kallings for eastern Europe—are so low profile that most people don’t realize they even exist. Lewis is the only one who makes headlines, not just in Africa but around the world. That’s because he knows how to court the media, he’s willing to work 20 hours a day, and he’s determined to spread uncomfortable facts about AIDS even if it means antagonizing his own employer.

Here’s what he said in a media briefing at the UN in March: “We came out of the Holocaust asking ourselves how we could ever live with the recognition that much of the world knew what was in those trains rumbling down the tracks to Auschwitz. We came out of Rwanda asking ourselves how it was possible that the world was inert in the face of a hideous genocide that everyone knew was taking place. It is my contention that years from now, historians will ask how it was possible that the world allowed AIDS to throttle and eviscerate a continent, overwhelmingly the women of that continent, and watch the tragedy unfold, in real time, while we toyed with the game of [UN] reform.”

Nevertheless, Lewis’s grassroots fact-finding, backroom negotiating and public lamenting is about to change. He’s saying goodbye to all that official diplomacy and quitting the unrelenting “part-time” job he’s held since May 2001. There was no set term, but five years seems long enough to have made a mark—for Lewis and the UN. First, though, he’ll address an estimated 20,000 delegates at the 16th AIDS Conference in Toronto this month. The conference theme, “Time to Deliver,” is meant to challenge governments and the UN itself to live up to their prevention and treatment commitments. It is actually a reprise of the chorus Lewis has been singing ever since he embarked on his odyssey as Kofi Annan’s representative.

As he makes the shift from public advocate to private citizen, he likes to joke that everything about him is “former,” making light of his previous careers as a political organizer (including for Tommy Douglas in 1956), politician (provincial leader of the New Democratic Party when Bill Davis was premier), labour arbitrator, media commentator and diplomat. But there’s nothing former about his commitment to social justice. He learned that from his father, David Lewis, federal leader of the NDP, and his mother, Sophie Lewis, and it’s been a theme coursing through his personal and professional life ever since.

He’ll take up a number of new assignments, including becoming a scholar-in-residence at McMaster University (where he’ll research and lecture on globalization) and taking an advisory position at the Harvard School of Public Health. Most significantly, he’s going to spend more energy on the Stephen Lewis Foundation, a charitable organization for AIDS relief in Africa that he founded in 2003 and which is run by Ilana Landsberg-Lewis, the eldest of his three children.