This Study, commissioned by the European Parliament’s Policy Department forCitizens’ Rights and Constitutional Affairs at the request of the Committee on CivilLiberties, Justice and Home Affairs (LIBE-Committee),takes stock of the maindevelopments that have occurred in the Schengen Governance Framework since2016. It analyses the legitimacy of a number of States’ decisions to maintaininternal border controls. Also, most recent policy proposals in the field of internalpolice checks are assessed in light of relevant EU legal standards. The paper alsoquestions the legality of the border walls and fences, which have been recentlyerected at the EU external borders and within the Schengen area.