  I propose an event study extension of Synthetic Difference-in-Differences
(SDID) estimators. I show that, in simple and staggered adoption designs,
estimators from Arkhangelsky et al. (2021) can be disaggregated into dynamic
treatment effect estimators, comparing the lagged outcome differentials of
treated and synthetic controls to their pre-treatment average. Estimators
presented in this note can be computed using the sdid_event Stata package.
