When I was a child, our family parties seemed, inevitably, to evolve into the entire family sitting in a large circle, chatting, talking, engaging one another. Circle just happened. In it, we're not leaders and followers, we're not bosses and employees or elected officials and voters - we're peers and equals. Circle facilitates conversation, sharing, and respect. Circle is foundational to participative processes - in various ways it's practice is central to participatory meetings and leadership. You can learn circle in 45 minutes and spend a lifetime mastering it.
Circle is foundational to most participative models.