Twenty years ago, a 12-year-old girl stood before government officials from most of the world's countries and pleaded for her future. Worried about pollution and overuse of natural resources on her finite planet, she begged, "If you don't know how to fix it, please don't break it." The occasion was the 1992 Earth Summit in Rio de Janeiro, which ended with the world's countries committing -- at least on paper -- to make environmental concerns a priority and eliminate unsustainable forms of production and consumption. Above all, delegates agreed that development must not jeopardize the welfare of future generations." Reminding the grownups in the room that their children and grandchildren deserved a decent life, too, the girl asked, "Are we even on your list of priorities?" Canadian Severn Cullis-Suzuki -- who pleaded on behalf of her generation then and who now has a toddler and an infant of her own -- will return to Rio in late June, when delegates gather again to try to map a sustainable course for the world's 7 billion people. The theme is one often raised by Pope Benedict XVI. During a Sunday blessing last November, he urged delegates to an international climate conference to consider "the needs of the poorest and future generations." A few days later, he told young Italian members of a Franciscan environmental group, "There is no good future for humanity or for the earth unless we educate everyone toward a style of life that is more responsible toward the created world." Many observers, however, are dubious that delegates in Rio will map a route toward that lifestyle. So far, negotiators have failed to agree on the summit document, which was supposed to be 90 percent complete before the summit begins; an additional writing session was scheduled May 29-June 2.