Does it matter what kind of professor a rec letter is from? If the individual is a lecturer or visiting professor, does that carry less weight than a tenured prof? NoAlso, what is the general train of thought regarding who writes the letters? I've heard it's better to have more from professors than from bosses. True? And how many letters are recommended?True. You want someone who can speak about your academics more than your professional experience. 2-3 letters, with one at most from a boss.Thanks so much for any help you can give.