in behalf of在美式英语中意为“为了……的利益；为着……；代表……”；on behalf of和on one's behalf 也是“为了……的缘故；为了……的利益；代表……”。表示“代表……”时，用on behalf of 较多。

• Please allow me, on/in behalf of my colleagues, to express our heartfelt thanks to you gentlemen for your warm welcome.
  请允许我代表同事们对你们的热情欢迎向各位先生们表示我们衷心的感谢。
• I'm writing on behalf of my mother, to express her thanks for your gift.
  我代表我妈妈写信，表达她对您赠送礼物的感谢。
• I felt pained not being able to do anything on your behalf .
  我为不能为您做任何事情而感到痛苦。
• The minister worked hard all his life in behalf of the poor.
  这位牧师一生为了穷人努力工作。
• The director will sign the document on/in behalf of the company.
  董事长将代表公司签署这份文件。