Have been using it on our 3 dogs for the past 2 weeks and they seem to take better to it than to the toxic stuff. The smell is strong, but mostly one gets a strong whiff of citronella, that's all. This is the first time since we got our dogs 7 years ago that we had an issue with fleas (no ticks) and this product, combined with the regular flea collar seems to help. The dogs are scratching a lot less now. I use it every 3-4 days, a spot between their shoulder blades does it, though it can also be put on the fabric collar, but l feel that this is too close to their nose and might make them feel overpowered by the smell.