Decision Making for Teams

In recent years we have put the focus on teams. Things like the whole team approach to testing have become a well known commodity and self-organizing team in scrum are something seen in many companies. One of the major parts of leadership is decision making. But have we adapted our decision making strategies going from a classic one person decides to the team decides?
My company has taken the team approach even further and we don't have any kind of bosses or leadership positions anymore.
In this talk, I will present situations where groups need to decide and what strategies and methods there are to make different kinds of decisions as a group. I will also talk about where at my company our ideas went wrong and where we had to adapt to come to decisions involving everyone without slowing down the decision process.