Yīmiàn dǎ qiáng, liǎngmiàn guāng.

一面打牆, 兩面光。

Lit A wall built by one side benefits both sides.

Fig One party's act can benefit both parties.

Note [Cf. the Qing dynasty writer Wang Zhuang's Wú Yàn Shī Chāo; note: liǎngmiànguāng as an idiom also refers to a person who always pleases both sides/parties; see also yī jiā qì qiáng below.]

Topics ACTIONS BENEFITS COOPERATION liǎngmiànguāng RECIPROCITY