My youngest daughter had been battling lice for 2 weeks- Rid didn't work at all after 2 treatments, and I felt awful putting the pesticides on her head. I was going crazy finding eggs and nymphs, and then I found Licefreee! I left it on for 90 minutes (it recommends at least an hour, but since it isn't a pesticide, I decided to leave it on longer). When I started combing through, I found dead lice which reassured me it worked. (after rinsing the Rid shampoo, lice were still crawling around). It's been 2 days now, and no sign of lice. I am still using the Robi comb ($30 at Walgreens which I also highly recommend- it detects live lice and kills them instantly).