Zope Interface is a package that forms a core part of Zope, an open-source web application server, and framework. It provides an implementation of "interfaces" in Python, which are similar to interfaces in other programming languages like Java. This enables developers to define formal contracts for Python objects, facilitating effective collaboration, better code organization, and ensuring adherence to specified behaviors or APIs in large codebases. The Zope Interface package is a foundational piece for building modular and component-based systems in Python.