Chapter 3 examines the first time period in the League's work, 1923–1925, which resulted in the publication by the League of Nations of the 1925 Report. The 1925 Report was drafted by seven Experts and presented a series of resolutions on addressing double income taxation and fiscal domicile. These resolutions provided the basis for the League’s later work which resulted in the 1928 Models. Chapter 3 explains the principles that guided the League’s Experts during their discussions, demonstrates that certain assumptions or conclusions which have been made about the League's work are erroneous, and provides insights into concepts that continue to be employed in modern double tax agreements and are the subject of ongoing discussions. For example, the Base Erosion and Profit Shifting action measures involve modifications to the permanent establishment concept. Chapter 3 reveals the original theoretical basis for the concept.