There are a few different types of stains that generally require dry cleaning in order to be removed. Some of the most common include: -Grease or oil-based stains: These can be tough to remove with regular laundry detergent and water. Dry cleaning is usually necessary to break down the grease and get the stain out. -Cigarette burns: Another tough one to remove! The heat from the cigarette can actually singe the fabric, making it difficult to treat at home. Dry cleaning is often your best bet here. -Protein-based stains (think sweat, blood, etc.): These can be tricky because they can actually set into the fabric if not treated quickly and correctly. Again, dry cleaning is often your best option as it will gently remove the stain without damaging the fabric itself.