20% azelaic acid cream is necessary to see results. Studies show less than this percentage doesn't do much. With that in mind, there aren't many that reach this percentage. Among the few, this one has the best texture and the fewest filler ingredients that you don't need to put on your face. Texture is important when it comes to layering skin care. This cream goes on dry and is a very beneficial treatment precursor to finishing moisturizers or oils. And it goes on very affably after a serum and toner. At night, it works fine after BHAs or AHAs, and before retinol moisturizers or oils. In the morning, it compliments niacinamide toner and helps control sebum as the aforementioned dry texture will create a matte finish for the day even if you moisturize again thereafter. It's also gentle, no burning and no interactions with sunscreen.