A mission statement answers three key questions:
A vision statement, on the other hand, describes how the future will look if the organization achieves its mission. A mission statement gives the overall purpose of an organization, while a vision statement describes a picture of the "preferred future." A mission statement explains what the organization does, for whom and the benefit. A vision statement, on the other hand, describes how the future will look if the organization achieves its mission.
Examples:
Centers for Disease Control Mission To promote health and quality of life by preventing and controlling disease, injury, and disability Vision Healthy People in a Healthy World