A conditional expression meaning 'all you have to do is...' or 'as long as (X) is done', indicating that one condition alone is sufficient.
連絡さえすれば、こちらで対応します。
If you just contact us, we'll handle it from here.
休みさえ取れれば、どこへでも行ける。
As long as I can get time off, I can go anywhere.
材料さえあれば、この料理は簡単に作れる。
All you need are the ingredients; this dish is easy to make.
説明書を読むだけで、さえすれば問題は解決するだろう。
Just by reading the instructions, the problem should be solved.