What's the best way to remove adhesive from concrete floors?

I dont know how much adhesive you are talking about but ';Goo B Gone'; is a great product that comes in liquid or spray gel and it removes anything sticky! You can also use brake cleaner to remove adhesive. If you have a large spot on the concrete go to Home Depot and buy some concrete paint and just pain over it. The paint has a sealer that will cover the adhesive and protect it from future messes as it seals the concrete underneath.