Much business and technical attention is being paid to the potential for new services in a ubiquitous computing environment. One of the probable features of these services is 'context-awareness', which is made possible by using information from the physical environmental through sensors. This paper provides an overview of the opportunities for new services and the requirements for middleware technologies. The middleware sub-theme group in Yaoyorozu-project has been focusing on the technological aspects for middleware in the ubiquitous computing environment. This paper, in addition, discusses user-centric requirements and middleware technologies for them clarified in 2 yeas activities of this project based on the trans-disciplinary science.