Interest-Based Negotiation, does it always work?

When I reviewed the conference agenda for the first day, I had no doubt about which concurrent session in the first slot I will attend: Through the Prism of Culture;Interest-Based Negotiations and the U.S. Air Force. Last semester I took a course on Interpersonal, Group and Systemic Conflict Resolution with C. Merchant where we primarily focused on Interest-Based Negotiations (IBN). It was a great course which gave me a lot of "food for thought" and ever since I have been "experimenting" with IBN (in smaller scale, mostly in interpersonal conflicts). I discovered that IBN doesn't always work in the other word you can't "do" IBN to people. They have to buy in for the process to work. Its especially harder to do with people from my own culture where negotiating with your family members and friends seems "rude" and inappropriate. So I was very curious to hear what the presenters; Dr. Gary Weaver, Kenneth Lechter and Dr. Stefan Eisen, who have been successfully using IBN in practice in a much bigger scale have to say about it. I guess I wanted them to built my confidence about the effectiveness of the IBN and its applicability. And I wasn't disappointed. I gained a lot from this session and got a great advise from K. Lecher how to convince people to buy-in into IBN. I will keep "experimenting" with this great tool to conflict resolution, IBN while keeping in mind that as Dr. Stefan Eisen pointed out IBN doesn't have to be to solution to all conflict situations, depending on situation or constraints you may have to choose another way of solving a conflict.