One of the thing that I absolutely hated about iPhoto is that unlike "Preview", there is only one "Rotate" button in the toolbar. It is possible to choose whether you want iPhoto to rotate clockwise or counter clockwise in iPhoto preferences, but it still takes time to change it all the time. What is happening is that when I take photos sideways, I always rotate the camera on the same side, but some friends and family rotate the camera on the other side. I end up with full rolls of pictures taken on one side and other rolls on the other side. Changing the preferences each time is much too long, so I resorted to right-click on the picture and choose "Rotate Clockwise" or "Rotate Counter Clockwise" from that drop-down menu. Well it turns out that there is a much quicker way of doing it. Watch the rotate button in the toolbar closely and press "Option". The rotate button will change direction! So you can set the one you use most often in the preferences and when you end up with a photo that needs to be rotated the other way, just press "Option" and click on that rotate button!