I was happy with how this mascara thickened and also lengthened my lashes. It didn't clump at all. However, I always curl my eyelashes with an eyelash curler and the problem was that after I put the mascara on, it seemed to straighten out my curled eyelashes almost immediately, and I've never had such a problem with another mascara doing that. If you aren't big on curling your lashes, this product would be perfect.