With the creation of computer networks in the 1970s came the birth of distributed network applications. Since then, there have been many applications that spanned multiple machines, but in the last 20 years no one created a serviceable network middleware package for developing highly effective distributed applications, that is, until now. This paper describes the design and architecture of T Spaces, a project at the IBM Almaden Research Center that fills the network middleware void. T Spaces embodies the three main characteristics of a useful mechanism for network programs, namely, data management, computation, and communication. Since it has the potential to connect any program to any other program on a computing network, T Spaces is an ideal platform on which to build a global computing services platform where any program or system service is available to any other program or service. In addition, its small footprint and JavaTM implementation make T Spaces an ideal platform for writing distributed applications for embedded and palm-top computers, thus forging a needed gateway from the emerging embedded and palm-top computers to established desktop and server computers.