Four words are at the heart of the interest based problem solving process:
The issue is the problem or subject area to be addressed.
A position is a proposed solution. Your position tells us what you want but not necessarily why you want it.
The interest is the underlying need, motivation or concern that may have to be addressed in order to reach a solution; you can tell an interest in part because there is usually more than one way to satisfy it.
An option is a potential way to address the issue, in whole or in part.