Mutual aid is understood as cooperation among individuals who engage in mutually beneficial behaviour, and is a core concept applied to group work practice in the field of social work. However, there is limited research detailing the specific processes of mutual aid and its application in successful group work practice. This qualitative study used focus groups with practitioners with experience facilitating groups in which mutual aid was observed. Analysis of participants' reports yielded four primary interconnected dynamics in which mutual aid was revealed: member factors, group factors, worker factors, and organizational factors. This paper describes these themes and their sub themes in detail, as well as implications for future research.