center on / center around / centre
The preposition after center, and the American spelling.
Center on means have as the central point: The talks centered on wages. A common error is to say center around, as in The talks centered around wages. A center is a single point, so things center on the point. For things that circle a point, use revolve around: The talks revolved around wages. The American spelling is center; centre is British.
Examples
UseThe dispute centers on the fee. (the fee is the central point)
AvoidThe dispute centers around the fee. (if you mean the fee is the central point)
Dictionaries now also list center around. However, many people still consider this phrase an error, and they judge the speaker who says center around.