Modality is considered as a semantic concept expressing such notions as possibility, necessity, probability, obligation, permission, ability, and volition. These different notions have given rise to two major distinct sub-types of modality as epistemic and root modality. Languages vary considerably in the way they realize each of these finer distinctions. This paper explores modality in Sinhala from a syntactic perspective. In particular, it attempts to answer such questions as (1) what are different types of modalities that can be observed in Sinhala and how are they represented? (2) Does the root-epistemic distinction in modality hold syntactically, and if so, what is their syntactic projection? (3) How does modality in Sinhala interact with the verbal system? Is there modal agreement in Sinhala? The theoretical alignment of the study is the generative syntactic theory expounded by Chomsky (1995 and thereafter), and within that, the cartographic framework proposed by Rizzi (1997), and Cinque, (1999). Data for the present study consisted of the grammatical judgments of native speakers of Sinhala. A sample of 10 native speakers representing different age groups was selected. This included 03 children aged between 8-13, and 6 adults in the age group of 30-60. The researcher too was considered as a member of the sample. About 40 sentences were presented to them with different ordering of modality particles in order to judge the scope properties and accuracy of such modal particles. The major conclusions of the paper are that the root/epistemic distinction holds in Sinhala not only semantically but also syntactically; epistemic modals occur higher in the structure while the root modals occur closer to the vP so that the former takes scope over the latter; Sinhala modals show hierarchy not only with respect to epistemic-root distinction, but also among each other; The –e suffix is as an overt reflex of an AGREE relation, i.e., a Spec-Head relation.