Poletto, C., and C. Tortora (2016). ‘Subject clitics: syntax’, in A. Ledgeway and M. Maiden (eds.), The Oxford Guide to the Romance Languages. Oxford & New York: Oxford University Press, 772-785. Introduction:Subject clitics — the topic of this chapter — are limited to a geographically circumscribed (and contiguous) group of varieties, found in the northern half of Italy (including northern Tuscany), southern France, and Switzerland. The fact that subject clitics are confined to a relatively small area should not, however, lead us to conclude that this is a comparatively simple area of syntax.On the contrary, the nature and extent of the variation, and the complexity of the theoretical questions involved, has challenged researchers for decades.