In the normal course of business, a company or a law firm may send out hundreds of letters to clients, prospective clients, vendors or various government agencies. With time running short for managers and professionals, it's not always feasible for the sender to personally sign the document after a staffer or secretary prepares it. For that reason, there's a generally accepted, legal convention for having a third party execute the signature.

Simple Correspondence

It's quite common for someone to prepare a business letter on short instruction from the sender. A law office, for example, may send out multiple copies of a simple letter, such as a request for a call in, to many different clients. If the sender is not available to personally sign it and getting the letter in the mail is imperative, an authorized employee or assistant may sign on behalf of the sender. The legal convention is to include the initials, "p.p.," which stand for the Latin phrase, "per procurationem," meaning "to take care of something," before the employee's signature. Procuration of correspondence means to sign it on someone else's behalf; a common alternative used for form letters is to use a signature stamp.

Methods and Procedure

It's acceptable to either type or write, "p.p." in front of your own signature, above the printed name of the sender. Or, you can place the sender's name above your own signature, which you must precede with "p.p." In the interest of consistency, and to prevent any misunderstandings, a professional or business office will set a standard procedure for signing letters on behalf of another.

Power of Attorney

The law also provides for an individual with a power of attorney to sign on someone else's behalf. A power of attorney allows an absent or incapacitated individual to carry on legal or financial activities with the assistance of a trusted relative or legal representative. The proper method, if you are authorized to sign by a power of attorney, is to first sign the principal's name and then your own, preceded by the word "by," to the side or underneath the principal's signature, with the phrase "power of attorney" or the initials, POA after your signature, for example, Joe Smith by Mary Jones, power of attorney. In some situations, the notarized and signed power of attorney form needs to accompany the contract, form or letter being signed.

Parents and Guardians

State laws generally provide that minors may not be held to legally binding contracts, with some exceptions. In a situation where a contract involves a minor, such as opening a bank account or drawing up a photographer's model release, the parent or legal guardian may be required to sign on behalf of the minor. In these cases, the parent or guardian follows his signature with the phrase "for and on behalf of," followed by the minor's name. The document may also require either the minor's printed or signed name on a separate signature line.