A polite expression meaning "it doesn't matter," "no problem," or "I don't mind," used to give permission or indicate no objection.
今行っても構いませんか？
Is it all right if I go now?
遅れても構いません。気を付けて来てください。
It's fine if you're late. Please come safely.
そのままの服装で構いませんよ。
Your current outfit is fine (you don't need to change).