Each Organization is set up with some goal and objective in mind. They always try to define their purpose in terms of statements. So in layman terms , The statement which clearly defines the purpose of the organization, that is what the organization wants to establish itself in the future is called as a Mission Statement. Apart from this , many companies take this as formal thing. But the successful companies always work on this. They always try to define it in Motivating terms. Many organization in the initial stage does not work for the statement , but as the company grows or add products to its product line and it grows in terms of revenue then it thinks of to give a Mission Statement by defining company's Mission in long term. So a good mission statement always gives a clarity for the organizations views and Purpose. Even from the successful companies Mission statement , it can be made clear that their it defines everything.

Some companies define it in terms of Product,Service and technology basis. Bur "A real mission statement should define the Purpose of the organization with Market orientation and customer needs". So depending upon the companies strength and how they can cater the customer to fulfil their needs should be the agenda for the statement.

Each Company should define itself before proceeding for the Mission statement. It should discuss some of the basic questions like

1. The targeted market - Who is the customer?
2. Customers needs and wants
3. Their Strength and Weakness to fulfill needs .
4. The way of their business.
5. Benefits to the stake holders or not.
6. Differentiation
7. It should be defined clearly and Understandable by every one.
8. it should be Motivating .
9. It should not too narrow or too broad.

For example: The Mission statement of Walt- Disney , who are in the business of making people happy is " Give ordinary folks the chance to buy the same thing as the rich people"

So from the above we can say that " A mission statement Gives the clarity of the objectives and Purpose of the organization".

About Author / Additional Info:
Philip Kotler - 11th edition.