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top brass; upper echelon; higher-ups; top management; upper reaches; top of the pile
問題が上層部に報告された。
The problem was reported to upper management.
上層部の決定に現場は従うしかなかった。
The people on the ground had no choice but to follow management's decision.
上層部からの急な指示変更で現場が混乱した。
A sudden change in direction from the top brass threw the team into confusion.