The box for Photoshop Elements for Mac OS has a note printed on it that says "Works with Apple iPhoto." This statement means that if you change the iPhoto preferences, you can open your images directly in Photoshop Elements when you double-click an image in iPhoto. You can also import an iPhoto catalog in the Elements Organizer.
Note: This statement does not mean that Adobe Technical Support provides any support for iPhoto. For support on iPhoto, contact Apple.