Mission: The unique purpose of an organization. The mission is a current profile of the organization and differs from the vision which describes the desired future.

A mission statement describes this purpose and serves as a guide for decisions, activities and outcomes. A mission statement answers the question, "Why do we exist?" You can think of a mission statement as a combination of what your organization does and how and why it does it.

Adapted from: http://www.cdc.gov/od/ocphp/nphpsp/PDF/Glossary.pdf