Prevent making different copies of my excel spreadsheet

Hi to you all,

I am having a spreadsheet that is critical to activities of my organisation. What can I do to stop people from making different copies on other computers from my central computer.

Thank you all.

Hey again,
Alternatively can anyone give me directions on how I can set up my spreadsheet such that no matter where my colleagues are they can update the database (spreadsheet) and changes made can be visible to all computers over a wireless network. What are my requirements? How can I set it up??
Your assistance will be greatly appreciated otherwise people are spoiling everything I make.... and well; Am about to get a nervous breakdown!!!