Program committee chairman

271 The Fourth Russian Seminar on Fiber Lasers took place in Ul’yanovsk on April 19–22, 2010. The event upholds traditions of the Seminars in Novosibirsk (2007), Saratov (2008), and Ufa (2009) [1]. The Sem inar was organized by the Ul’yanovsk State University. Components of fiber lasers, various configurations of fiber lasers and amplifiers, nonlinear phenomena in optical fibers, applications of fiber lasers in communi cations and technology, and fiber optic sensors were the Program highlights. More than 100 participants from Novosibirsk, Snezhinsk, Kazan, Samara, Sara tov, Ul’yanovsk, Moscow, Fryazino, and other Russian cities presented 70 reports.