All RIEDEL glasses are dishwasher safe! Riedel exclusively recommends Miele dishwashers; laboratory testing has shown that Riedel glasses have an estimated lifespan of 1,500 washing cycles when washed properly in a Miele dishwasher. This is the statistical equivalent of the average number of washes during a 20 year timeframe. To avoid scratches: Avoid glass contact with other glass or metal. If available use a stemware rack. To avoid stains: Use soft water (low mineral content). To remove stains: Use white vinegar. If washing by hand, wash the glass under warm water (use detergent and rinse the glass carefully). Wash cleaning towels at boiling temperature (to kill bacteria) with odorless soap. Never use linen softener, when rinsing your cleaning towels (to avoid grease film on surface). To polish the glass: Use two towels, never hold the glass by the base to polish the bowl as the stem could snap due to mishandling. Avoid storing glasses in kitchen cabinets next to items with a strong odor, as this can taint the glass and have an effect on the wines aroma.