Following Hopper & Traugott (2003 [1993]: 232), grammaticalisation can be defined as “the change whereby lexical items and constructions come in certain linguistic contexts to serve grammatical functions and, once grammaticalized, continue to develop new grammatical functions.” Grammaticalisation processes have not been studied very extensively in sign languages yet. Pfau & Steinbach (2006) give a very interesting survey of studies that have focused on grammaticalisation processes in sign languages, but Flemish Sign Language (VGT) was not one of them. Within the Deaf community in Flanders about 5000 - 6000 people (Loots et al. 2003) claim to have Flemish Sign Language as their first or principal language. After lengthy negotiations, VGT was officially recognized by the Flemish Parliament in April 2006. VGT clearly is a fully-fledged sign language in its own right, and is genealogically related to amongst others French-Belgian Sign Language (LSBF), French Sign Language (LSF), American Sign Language (ASL) and Sign Language of the Netherlands (NGT). The common ancestor of these daughter sign languages is Old French Sign Language (OFSL). However, it is impossible to use historical data to look at grammaticalisation paths since there simply are very few historical grammatical data as OFSL was never written down. Consequently, the method to be used is that of internal reconstruction which is a procedure for inferring part of the history of a language from material available for a synchronic description of the language on the basis of paradigmatic allomorphy.