Ceramic mugs can be washed in the dishwasher, while porcelain must be washed separately by hand. The handle of the cup must be moved away from any other utensil so as not to damage it.
The cups are only recommended for cold drinks and are dishwasher safe on the top shelf (thanks to Starbucks). I use these mugs every day and are very easy to clean and dishwasher safe. Starbucks sells reusable coffee and travel mugs that you can use in their stores for a small discount.