Grouts have evolved substantially over the years and have new and improved stain resistant options. Standard cement grout is porous and requires maintenance, including regular sealing. Admixes are available to mix in during installation that help aid in flexibility and/or stain resistance. Urethane grouts add even more stain resistance and come premixed in buckets. They do cost a bit more and have a tendency to be a little more challenging to work with. Epoxy grouts are the most impervious grouts and offer optimum stain resistance. These are more difficult to work with as it spreads like an adhesive, not like a cement grout. When cleaning your grout, be sure to use clean, clear water and a small amount of cleaning solution. Using dirty mop water on unsealed cement grout is sure to cause your grout to discolor.