A project recommendation letter is a letter typically written by a superior in an attempt to get an employee involved in a particular project or line of employment. If you're in the position of writing a project recommendation letter for an employee or colleague, it is important to remember that the letter may be all that stands in the way of that person achieving her goal. Because of that, it's important to write the letter the appropriate way.
Obtain all the required information from the person you are writing the recommendation letter for that you need to actually write the letter. This includes the name and position (and address, if you're mailing the letter) of the person the letter will be addressed to, as well as the project and description of the position the person is trying to get.
Begin your letter by detailing who you are, and how you are related to the person you are writing the letter for. If you're writing a letter for Hank Kingsley and have been his supervisor for 10 years, detail that in the opening of the letter. This will allow the reader to have the context necessary to understand why this letter matters.
Detail the qualifications, as they are related to the project in particular, of the person for whom you are writing the letter. If the project involves marketing, for example, detail the person's marketing experience and write about her successes. Don't include irrelevant information. If the project involves marketing, don't write about how the subject of the letter is really good at filing and making copies.
Sign and date your project letter of recommendation. Seal the letter inside an envelope. If you're mailing the letter, address the envelope and put it in the mail. Otherwise, give the envelope back to the person you are writing it for, allowing them to hand deliver it to the project leader or supervisor.