This chapter aims to deconstruct the concept of terrorist financing and its components and grab its implications. By presenting different theoretical approaches, it examines the importance of the financial aspects of terrorism and its dynamics. The chapter provides the definition of ‘terrorist financing’ and explains its importance for terrorist organizations. It explores terrorist financing from a theoretical perspective, and different funding models so as to understand terrorists’ financial activities. The chapter explains the current financial sources and methods utilised by terrorist organisations and illicit financial transfer methods. ‘Terrorist resourcing’ which is a broader concept includes the financing of terrorism. This term can be defined as the acquisition and supervision of all required goods for terrorist groups. Even though conducting a terrorist attack may need small amounts of money, running a terrorist organisation for a special purpose requires considerable financial resources and operational capacity.