授权书(或授权委托书)在英文中有两种形式，即Letter of Authorization (LOA) 和 Power of Attorney (POA),而且英文授权书在使用上是有一些区别的。一般来说，Letter of Authorization比较通用，几乎可以用于各种形式和各种需求时的授权;而Power of Attorney的使用比较严格，被授权人应为律师(Attorney)。 在招标投标书翻译时，一般应选用Letter of Authorization。

　　LETTER OF AUTHORIZATION

　　I, the name of legal representative, the undersigned legal representative of the company name of the bidder, hereby authorize the undersigned the name of the duly authorized representative to be true and lawful representative of the Company from the date of this letter of authorization to act for and on behalf of the Company with legally binding effect for and in respect of to sign the bids. And I acknowledge all the contents contained in the bids signed by the authorized representative.

　　It is hereby authorized.

　　Name of the Company: (official seal)

　　Legal representative: (signature)

　　Authorized representative: (signature)

　　Date: