# using [] in the caption of the subfigure

The `subfigure` caption uses []. Because of that, I am unable to use [] in its caption.

``````\subfigure[ This [] is important]
``````

How do I use the brackets in the caption of the subfigure?

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The problem is that LaTeX views the closing bracket as the end of the short title (optional argument). As suggested by David Carlisle, you can hide the square bracket in a brace pair: `{]}` should do the trick. (David put the entire optional argument in braces, but this is not needed.) – Marc van Dongen Sep 14 '12 at 8:53

For (almost) any latex optional argument you can use `{}` as in
``````\subfigure[{This [] is important}]
To hide the inner `[]` from the argument scanning.