Writing a letter to a dignitary can be a very complicated matter. You must strike just the right tone of respect without fawning. In addition, you must know the appropriate salutation to use and ensure that the person's title is correct in the letter and on the envelope. Not all dignitaries of equal rank are treated the same. For example, the president of a republic is addressed as "Excellency" in the salutation, whereas the president of the United States is addressed as "Mr. President."
Research the recipient's title. Is she a state senator, a representative or something else? You do not want to be incorrect, because this will make you look uninformed and reduce your credibility.
Start the letter by typing your address but not your name. Skip a line, and type the full date. Skip an additional line, and type the dignitary's official address and his or her physical address. For example, if you were writing to the queen of England, you would write: "Her Majesty the Queen," followed by the address of her home. As of 2011, the constitutional monarch is Queen Elizabeth II. Her name is actually Elizabeth Alexandra Mary, but that is never how she is addressed.
Start the salutation. Often this is different from the address. For example, if you were writing to the queen of England, you would use either "Madam" or "May it please Your Majesty." Follow both with a colon.
Type the body of your letter. Be careful to maintain a respectful tone throughout. Whether or not you are a subject or citizen under the reign or term of the dignitary, treat him or her with the respect appropriate to the position.
End the letter with the closing statement that corresponds to the dignitary's title. For the queen, a subject should sign off with "I have honor to remain, Madam, Your Majesty’s most humble and obedient subject," followed by the subject's typed full name and signature above that. However, for the president of the United States, you need only write "Respectfully," followed by your typed name and signature. When writing to a former president, "Sincerely" suffices.
Address the envelope using the same formal address that appears in the letter. For example, for a former president of the United States, you would write "Honorable (Name)," followed by the physical address. For the queen of England, you would type "Her Majesty the Queen," followed by the physical address.