text: ITTW has a history of a decade. The conference was started from 2006 in ULB, Brussels by the effort of Prof. Oleg A. Kabov (RAS). The conference is annual and the latest and state-of-art topics of the two-phase systems are discussed among the researchers in the world working in the same discipline. At the same time, the opportunities of international collaboration in the ground-based or space experiments are given to all participants including young researchers through the communication during the conference. In the past, ITTW was held in Japan two times, i.e. 2007 and 2010 in Kyoto. It is our great pleasure to welcome you to the commemorable 10th conference held again in Japan. The joint conference with ISPS-6 will become a good opportunity to develop the application of the researches on two-phase systems by a new strategy keeping the established conference style of ITTW unchanged.