Our roots for negotiation extend far deeper and farther back than we often recognize. Sapiens: A Brief History of Humankind by historian Yuval Noah Harari (Vintage, 2015) presents all human beings' collectively exceptional skills. These skills make us innately proficient at extraordinary communication, such as negotiation.

Culture in negotiation is more than the familiar interpretation of national entities. The Righteous Mind: Why Good People Are Divided by Politics and Religion by psychologist Jonathan Haidt (reprint edition, 2013) provides the attuned negotiator an additional, and indeed required, dimension for understanding behavior.

Negotiators face a dizzying array of behaviors. When Cultures Collide: Leading Across Cultures by communication consultant Richard D. Lewis (3rd Edition, 2005) focuses on the most familiar definition of culture and, as such, is a valuable resource for developing negotiation skills.

Negotiators seeking successful and lasting partnerships need reliable guidance to improve their skills. Bargaining for Advantage: Negotiation Strategies for Reasonable People by business professor G. Richard Shell (Reissue ed., 2000) is my second bookend reference in this category.