In this paper a prototype Greek text to Greek Sign Language (GSL) Conversion System is presented. The system is integrated into an educational platform that addresses the needs of teaching GSL grammar and was developed within the SYNENNOESE project (Efthimiou et al. 2004a). The detailed implementation of the language-processing component of a Greek Text to Greek Sign Language Conversion system is provided, focusing upon the inherent problems of knowledge elicitation of sign language grammar and its implementation within a parser framework. It is based on a Sign Language dictionary (Efthimiou et al. 2004a) database of coded GSL knowledge. The proposed system has been designed and implemented after considering most state-of-the-art Sign Language machine translation or Conversion systems, such as Vsigns (Papadogiorgaki et al. 2004), ZARDOZ (Veale et al. 1998) and SignSynth (Angus et al. 2001), and taking into account their advantages and disadvantages. The overall architecture is innovative since other existing systems either do not consider the Greek Sign Language or they cannot be effectively applied on sentences but just on single words. The system is demonstrable on any conventional PC.