Baby wipes are my best friend. I go through many of them, especially in allergy season, wiping the dogs down when they come inside, until the baby wipe comes off clean. One of the most effective control measures I've found, though, is to fill a bucket about halfway with warm water, and "dunk" each doggie foot in the water and rub it good before I let the dogs in, after they've romped in the dust or mud. It seems that more "junk" comes in on their feet than any other way, and so that has worked very well! So...we have regular foot washings on the back deck!