This issue presents frequently - a list of possible reasons and some ideas to approach the impasse.

In some matters of relatively high conflict, a code of conduct may provide some guidelines to make communication better. 

Although the dominant paradigm is the "shuttle diplomacy," there are real and significant benefits to negotiating directly - with the aid of the mediator. 

 

In additional to improved communication and understanding, an analytical approach may help parties reach better agreements.

What they are and how to use them. Obtaining a nonbinding evaluation of the case.

In some cases, forming and using technical teams made up of experts from opposing parties can simplify the conflict and the search for solutions.