We recommend the use of water-soluble marking pens, like those used with overhead projectors (wet-erase markers) with our game mats. Vinyl is a very porous material and any marks make by dry-erase or permanent markers will stain the mat. Its the trade off for having a flat surface that rolls versus a laminated surface that may curl or crease. But I'm a bit old school, I still have and use my wet-erase mat that I purchased from an ad in Dragon Magazine in 1984, so I'm a bit partial to wet-erase.