My PDFs don't open in iBooks they open in preview

Greetings Alain,

Thank you for participating in the Apple Support Communities.

If you want to set iBooks as the default application for opening PDF files, you can use these steps from OS X Yosemite: Choose an app to open a file:

Permanently change the app used to open a document

1. In the Finder, select the document, then choose File > Get Info.

   You can also Control-click the document, then choose Get Info.

2. In the Info window, click the disclosure triangle next to “Open with.”

3. Click the pop-up menu, then choose the app.

   To open all documents of this file type with this app, click Change All.

Best Regards,

Jeremy