At the core of corrective surveillance lies the excessive deficit procedure. This chapter employs theories of bargaining to explain the opening and continuation of this oversight and political economy theories of public spending to explain its consequences for national public finances. Whether a procedure is launched or concluded is shaped mostly by factors related to compliance, bargaining, and national pressures, such as past and expected fiscal performance, ideological positions of governments and commissioners, and public opinion in the surveilled country. As for the consequences of oversight, surveillance has significantly shaped national budgetary processes, counterbalancing the national pressures governments face when they set their fiscal policies. The impact of corrective surveillance offsets that of a two-year shortening of expected government duration, the addition of one party to a government coalition when debt is high, or a leftward shift in government ideology when the risk of replacement is low. Moreover, estimates from exact matching on treatment histories indicate that these effects peak after four to five years.