Pervasive computing is an emerging computing paradigm, which is expected to be part of our everyday life in the foreseeable future. The coordination among heterogeneous devices, services, and software agents will be vital for ensuring the success of their interactions. Tuplespace (TS) offers a coordination infrastructure for communication. With pervasive computing environment which is characterized as an open and dynamic distributed system become more ubiquitous, autonomous, and complex, this can pose some limitations to TS. In this paper we introduce Semantic Tuplespaces (STS) based on a combination of Semantic Web technologies and tuplespace computing. It acts as a middleware to enable communication and coordination based on the principle of publish and retrieve of semantic information. We describe overview of the conceptual model and discuss the necessary extensions to the original tuplespace. An initial version of the STS prototype system has been implemented based on Jena and Pel...