We buy the dog shirts and by layering we've been able to keep most the ticks away. We have a horrible tick population here so any amount of reduction is great. We also use metal tick tags and wondercide spray. There are topical and ingestable tick prevention but they don't work well on ticks either and have caused a ton of health problems in our dogs and others I know. I will continuing using the dog shirts. One piece of advice, is the shirt scoots down on our big dog so I make a small hole in the material on the top beneath the tag and string her collar through the hole, it holds the shirt in place much better.