Is there a way to secure a powerpoint presentation against edits?

Three options I can think of:

  1. Under the Office menu|Prepare, you can select Mark as Final, which restricts editing. Note that this is not security based as any user can turn it off, but it's a reasonable indicator.
  2. You could set a Modify password under Tools|General Options on the Save As... dialogue. enter image description here

  3. You could save as another format such as PDF or XPS as RichardM suggests.

Why not save the presentation as a PDF? Some formatting may not work out perfectly, but links will still work and it will not be editable as a PowerPoint file.