When someone monopolizes session time, I first acknowledge their enthusiasm. Then I gently redirect by using time checks or asking them to hold thoughts for later. I also start setting clear expectations at the beginning of each session about balanced participation. Sometimes these participants just need to feel heard, so I might acknowledge their point briefly and move on. Other times, I'll give them a specific role like summarizing others' points, which channels their energy productively. The key is redirecting without making them feel dismissed. Addressing it early prevents resentment from other participants and keeps the whole group energized.