Given the long tradition of viewing signed languages through the lens of spoken language, linguists have risked overlooking linguistic properties unique to signed languages. This presents a challenge/opportunity for linguists who work with signed languages. Linguists typically seek to explore properties that appear at the outset to be either modality independent (found in both spoken and signed languages) or modality specific (attested to in only spoken or signed language). However, they do not often explore variation across different signed language systems. This omission presents a fertile area of research for signed language typology, that has the potential to inform us regarding typological variation in visual-gestural languages and the implications of these differences.