Given the social nature of digital gaming, an investigation into social processes underpinning the experiences within social contexts of play is greatly warranted. The current research explored the underpinnings of “group flow” within cooperative-based gaming. In particular, this was intended to provide insight into the social processes which facilitate flow experiences in these contexts. This was achieved through a questionnaire in which gamers (N = 76) provided retrospective open-ended accounts of flow during cooperative gaming. Additionally, quantitative data was obtained on flow and post-gameplay mood within this experience, as well as in solo gaming for comparative analysis. Thematic analysis of the qualitative responses revealed a number of factors which determined the experience of flow. These were; effective communication and team-work and task relevant knowledge of group members. Additionally, although flow was found to be lower in cooperative versus solo gaming, no differences in post-gameplay mood were observed. These findings aid conceptual development of facilitators of group flow in cooperative gaming, with insights into how this may extend to other cooperative activities. Additionally, they also provide new practical insight for representatives in the gaming industry on how gaming may be developed with the aim of promoting positive shared group experiences.