Linda,
If the hyperlink is to the same thing, then Yes you can add one link to all your slides in a single presentation.
View > Master > Slide Master
Add your hyperlink here (or add an action setting...right click any object)
View > Master > Slides when you have finished.
Normally all your slides will follow what is on the master slide
Cheers
TAJ Simmons
microsoft powerpoint mvp
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