No mascara that I've yet to try can stop my mascara smudging. From all the fancy high-end ones to the Japanese apocalyptic ones, to tubing mascaras or whatever. I'm still searching, but in the meantime, this does a decent job of stopping my mascara from smudging. I've yet to test this in the height of summer, but so far so good. I also like that it doesn't clump my lashes together after the time I've spent applying mascara beforehand.