Despite their long history and growing influence, social work professional organisations (SWPOs) remain underexplored in social work research. Created and fully or partly governed by professionals for professionals, SWPOs comprise millions of practitioners worldwide – some groups having existed for around 100 years – to develop activities that are increasingly relevant for practitioners, users, schools of social work and policy makers. This edited volume provides the first comprehensive, comparative analysis of SWPOs in 15 countries, bridging Global North and South perspectives. Using an interdisciplinary framework, it offers an evidence-based typology of SWPOs, illustrating their evolving role as collective actors in social work. Essential reading for educators, researchers and students in social work, this book speaks directly to the global community of SWPOs.