These boards can be washed with warm water and a gentle soap, but never submerge them in water and always dry them thoroughly. Never place them in a dishwasher. After a few uses, a food grade mineral oil and/or beeswax should be reapplied to preserve the finish. (I've included links below for the mineral oil and beeswax that I use.) Be generous with the oil. Apply the oil directly to the board, flooding the surface and allowing it to soak in for several hours. Dry the surface with a clean soft towel, removing any excess oil. After several hours of drying time a coat or even two of beeswax can be applied according to their directions. Buff with a dry soft towel..