I took Melatonin for years and I'm back on it now.

Shortened version of the story: I was prescribed Ambien 11 years ago and my body got addicted to having a sleep med, I couldn't sleep without a sleep aid. It took 6 years to wean into not using a sleep aid of any sort, with the last 2 or 3 years being various doses of Melatonin. About 2 years ago, my doctor (stupidly) prescribed me something that also worked as a sleep aid, even though I specifically said I wanted to avoid any meds that worked in any fashion as a sedative. Well, on that med my body began requiring sleep aids again. For the last couple of months I've been back to just Melatonin.

So does Melatonin work? Yes. Does it always work for me? No. If I'm wide awake then it doesn't do anything for me. If I'm the slightest bit tired and I give it enough time (say 2-2.5 hours), it works. The more tired I am, the better it works for me.