People will not trade away their identity or their security. Identity and security are so fundamental, so necessary to all human satisfaction, that people will do almost anything, even things that violate fundamental norms, or diminish their ability to attain their interests, in an effort to obtain their fundamental needs. A second difference is that needs are usually not mutually exclusive. While interests may be structured in such a way that only one side can get what it wants, needs are usually mutually supporting. Similarly, if one's own identity is secure, then there is no need to threaten another's sense of identity.
Values are also fundamental beliefs that are non-negotiable.
Values determine how we understand the world and how we respond to it. As with needs, if one's values are questioned or threatened, one is likely to respond strongly to defend one's values. Transformative forms of dispute resolution, however, tend to deal with values and needs much more extensively, believing that having an understanding of those issues must preceded any work on interest negotiation.