It's quick and easy to ask for a LinkedIn recommendation or to ask someone if you can give out their phone number to prospective employers.
However, depending on the job you are applying for, you may also need written reference letters to provide to prospective employers. Some companies even want them prior to scheduling an interview. I've started to notice "recent reference letters" specified in job postings, so the letters you got years ago aren't going to suffice.
Recent reference letters shouldn't be any more than two (or three at the most) years old. They don't all need to be from your employer. You can ask colleagues, vendors, clients or anyone else who can attest to your professional clients.
Employers usually ask for three reference letters and it's a good idea to get them prior to starting a job search. That way you won't have to scramble when you're asked. Here's how to ask for a reference letter.
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