Our project aims to establish whether targeted provision of constituents’ preferences increases the responsiveness of delegates to the Vietnamese National Assembly (VNA). Utilizing a randomized control trial (RCT), we assign legislators to one of three groups: (1) those briefed on the opinions of their provincial citizenry; (2) those presented with the preferences of local firms; and (3) those receiving no informational treatment what- soever. We also used a saturation design, applying the treatments to differing shares of delegates across provinces. After the summer 2018 session, we collected behavioral data on delegates from the legislative session, including answers to a VNA Library survey about debate preparation; the identity of speakers in group caucuses, query sessions, and floor debates; and the textual content of those speeches. We find consistent evi- dence that citizen-treated delegates were more responsive, via debate preparation and the decision to speak; evidence from speech content is more mixed. More speculatively, we find little evidence of spillover from treated to untreated delegates, but substantial evidence of treatment reinforcement. Citizen-treated delegates grew more responsive as more of their peers possessed identical information.