Both A and B / Whether A or B
Used to emphasize that both items mentioned are of the same importance or relevance, commonly used in formal contexts.
Examples
彼の提案といい、実行計画といい、どちらも非常に有効だ。
Both his proposal and the implementation plan are very effective.
環境問題といい、経済の健全性といい、どちらも重要な課題だ。
Both environmental issues and economic stability are important challenges.
文化といい、歴史といい、私たちにとって大切な遺産だ。
Both culture and history are invaluable heritages for us.
Quick check
環境問題___、経済の健全性___、どちらも重要な課題だ。