The flexibility/stability tension is a key challenge for purpose-oriented networks, especially salient with network participation. Because of the voluntary nature of networks, it is common for network participation to fluctuate, with participants entering, leaving, and returning over time for a variety of reasons. This fluctuation may challenge the stability that is key to network effectiveness. Yet, despite the salience of this tension, we know little about managing the ebb and flow of network participation. Driven by phenomenon-based theorizing, we draw on longitudinal participatory action research to examine participant attendance and contribution in monthly workgroup meetings over a four-year period of an early child education network. Combining interviews (n=5), meeting attendance tracking (n=37), and meeting observations (n=30), we identify six types of flux stemming from individual, organizational, and system forces. We find these forces of flux support both flexibility and stability. Highlighting the duality of flexibility and stability, we explain how flexibility at one level may result in stability at another and vice versa. Our findings contribute to a greater understanding of how stability and flexibility are both valuable for networks and thus, the need to embrace the ebb and flow of participation.