Intelligent search techniques are required to deal with complex games that have very large state spaces. In the project, various successors of proof-number (PN) search are investigated and developed for application to complex games. * Progress in 2003. In addition to his final experiments on using PN-search variants, Mark Winands performed experiments on using several forward-pruning schemes. A large part of the thesis has been written. Mark Winands visited Shizuoka University from June 16 until September 15. Further, Mark Winands continued his work on enhancing the strength of MIA IV, our Lines-of-Action program. MIA IV participated in the 8th Computer Olympiad, November 2003, and achieved the gold medal. * Future work. In 2004 Mark Winands will defend his Ph.D. thesis. Moreover, he will defend his title of reigning computer-LOA champion at the 9th Computer Olympiad in Ramat-Gan, Israel, using an enhanced version of MIA.