IMO, Clarins’ Double Serum ranks up there with Chanel No. 5, MAC Ruby Woo, Maybelline Great Lash, and other hall of fame beauty products. The luxury beauty house of Clarins was founded in 1954 by Jacques Courtin-Clarins (the Courtin family still independently owns the brand today), but it wasn’t until 1996 that Clarins unveiled the Double Serum, which, until then, had been sold as two separate bottles for the consumer to mix at home. Double Serum would eventually become one of the most popular products in the Clarins œuvre, with the name being a nod to the bottle’s innovative dual-chamber design: One half of the bottle housed the water-soluble formula, the other, an oil-based concentrate. At the press of a pump, the two dispensed equally, allowing for maximum potency and efficacy.