According to the metafunctional hypothesis, there is a non arbitrary relationship between three major kinds of linguistic structure–‘wave’ (sequence and periodicity), ‘field’ (intonation) and ‘particle’ (constituents) and the core meanings they typically express (textual, interpersonal and ideational, respectively). Furthermore, every act of meaning using a linguistic semiotic system is said to simultaneously encode and express all three types of meaning. This paper looks at Auslan (Australian sign language) in the light of this hypothesis and tries to show that the substantive difference between language in the two media (signed and spoken) is not the simultaneity of codings in the former (as frequently maintained in the sign linguistics literature); rather, it is the availability of space in a visual-gestural language which gives it an extra dimension in which to configure sequence and order. Examples are given in which sign strings instantiate a highly complex spatio-temporal matrix (rather than simply a ‘sequence’ or ‘order’) which involves not only constituent signs but also groups of signs and/or ‘fields’ delineated by expression.Space is a resource unique to sign languages and has rich potential for encoding various types of meanings when combined with the general resources of wave, field and particle. However, the very availability of space as a substance or vehicle of linguistic expression is also a function of the fact the sign languages are quintessentially face-to-face languages: a fact that may influence, and even constrain, the linguistic system in other ways.