I have been a hairdresser for 25 years and my number one concern has been coloring resistant gray hair. Gray Riddance is a God-send. I just spray it on and it changes the gray to subtle light brown highlights. I even use a temporary rinse the same color as my natural dark hair over the hightlights created by Gray Riddance. The rinse lasts longer and when it fades no gray shows, just highlights. Great product.