The aim of the chapter is, against a background of reforms of the financial system and financial regulations in Poland, to characterize the main activities of supervisors and changes in financial regulations in Poland, being the aftermath of the global financial crisis. It also provides a short description of the Polish regulatory framework and describes subsequent changes of regulations resulting from adjustments to changes in the European Union (EU) directives, connected with the accession process. The chapter presents the main changes in the regulatory frameworks, enforced in a way by crisis events and resulting from response to them from, respectively, European and domestic regulators. The process of adjustment of Polish law was very dynamic, since regulations regarding the financial sector in European law have been frequently changed. The Markets in Financial Instruments Directive (MiFID) has been introduced into Polish law through the Act on Trade in Financial Instruments together with its implementing provisions.