This document is a dissertation submitted for a Master's degree in European Union Law at King's College London in 2015. It analyzes regulatory changes in the European payment services industry brought about by the revised Payment Services Directive 2 (PSD2). PSD2 aims to update regulations to reflect technological innovations and new payment practices while maintaining security. It broadens the scope of regulated payment services and access to payment accounts. The dissertation examines key issues around balancing security, innovation, and the fundamental freedoms within the European Union in the new regulatory framework under PSD2.