How to apply develop settings to multiple images at once in Lightroom?

Question

I'm in the Develop module in Lightroom 3. The secondary monitor shows a grid with multiple photos selected. When I change a develop setting, e.g. exposure +1, the setting is only applied to one of the selected photos (the one shown on the primary monitor). Is there a way to make Lightroom 3 apply the change to all photos selected in the grid?

Answer

Yes: hold down command (ctrl on windows) and the 'Sync' button on the bottom of the development pane (i.e., the lower right) becomes 'Auto Sync', which will apply any changes to the whole selection.

The switch on the sync button toggles Auto Sync on and off more permanently.

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