Consultation or discussion among several people to reach a decision; deliberation (often formal).
重要な案件は合議のうえで決定します。
Important matters are decided after consultation/deliberation.
その問題については役員で合議した。
We consulted with the executives about that issue.
合議制を採用して意思決定を行う会社もある。
Some companies use a system of collective deliberation to make decisions.