Welcome to the 5th International Symposium on Ultrafast Photonic Technologies (ISUPT2011), which is held at the Fraunhofer Heinrich-Hertz-Institute (HHI) in Berlin, Germany on September. 15th-16th, 2011. ISUPT is intended to provide a forum for researchers working on ultrafast photonic technologies including ultrahigh-speed optical communication, optical metrology, lasers, bio-medical technology, and advanced measurement technologies. The first ISUPT (originally named as "Europe-US-Japan Symposium on Ultrafast Photonics Technology") was held at Makuhari in Japan in 2003, followed by the 2ndsymposium at University of St. Andrews in 2005 hosted by Profs. Wilson Sibbett and Alan Miller,  the 3rd symposium at MIT in 2007 hosted by Prof. Erich P. Ippen, and the 4th symposium at RIEC, Tohoku University in 2009 hosted by Prof. Masataka Nakazawa. The 5th symposium, ISUPT 2011, consists of 21 invited presentations by eminent speakers from U.S., Europe, and Japan. The latest advances in ultrafast photonics are presented, and future directions for research and development will be discussed among the leaders in this field. ISUPT takes place just before ECOC 2011 (Sep. 18th-22th) in Geneva, so you can combine both events with minimum cost. Enjoy a few days in Berlin, a city which is renowned for its architectural monuments, museums, green oases and nightlife galore. This symposium is sponsored by RIEC, NICT, AIST, HHI, u2t Photonics and the VICTORIES program. The symposium is open to the public and free to all participants.