Pre-print, Working paper: This paper studies how the introduction of multilateral automatic exchange of information (AEOI) in 2017 affects tax compliance. Exploiting rich tax data, variation generated by the interplay of the Swiss tax amnesty with the AEOI, and difference-in-differences designs, I document substantial compliance responses. At the macro level, about 107k taxpayers (2% of all) were pushed to participate in amnesty by the AEOI. Together, they disclosed around 35.2 billion Swiss francs in hidden assets—more than 5% of GDP. I show that the behavioral compliance responses persists at the micro level. Once a tax evader enters the amnesty, their wealth on average increases by 50% and remains at this higher level in subsequent years (relative to the control group). Lastly, I provide evidence that tax evasion is widespread and more evenly distributed in Switzerland than in other European countries—which is consistent with Switzerland’s lack of third-party reporting prior to the AEOI.