Bilateral free trade agreements and bilateral investment treaties have evolved enormously since the former were signed. The changes consist primarily in covering a broader spectrum of issues which, in addition to the rights and obligations of investors and host countries, define a new axiological basis and further values implemented through the agreements. What has also changed is the legal environment in which the agreements are implemented, including the regulations specifying the competences of the EU member states to sign free trade and investment protection agreements. New multilateral investment agreements have also emerged in global trade. The approach to entrusting investment disputes to arbitration courts has changed. The aim of this study is to anticipate possible scenarios for further regulation of (existing and future) investments made by UK investors in EU countries and vice versa after Brexit.