When the Kyoto Protocol took effect on February 16, the Pew Center on Global Climate Change created this special section on its Web site to help readers understand the implications. The site looks at what it means now that the protocol has gone into force, its history, and what happens next. Find analysis and reports, a Kyoto Q&A, glossary of key terms, and downloadable documents such as "Implications for U.S. Companies of Kyoto’s Entry into Force without the U.S."