Alberto Morillas was born in 1950 in Seville, Spain, and relocated with his family to Switzerland as a child. He later studied for a couple of years at the École des Beaux-Arts in Geneva before finding his way into perfumery — by his own account, he was largely self-taught in the craft rather than formally trained as a chemist. An article about Jean-Paul Guerlain in Vogue is widely credited with turning his attention toward scent as a profession.

In 1970, at around age twenty, Morillas joined the Swiss fragrance and flavor house Firmenich, where he has spent his entire career (the company later merged with DSM to become dsm-firmenich). His breakthrough came in 1975 with Must de Cartier, the jewelry house's first fragrance, and he went on to become one of the most prolific noses of his generation, eventually rising to the rank of Master Perfumer.

Over five decades he has composed a long run of best-selling, category-defining scents, among them Calvin Klein's CK One, Giorgio Armani's Acqua di Giò, Kenzo Flower, Estée Lauder Pleasures, Marc Jacobs Daisy, Bvlgari Omnia and Goldea, and Gucci Bloom, alongside dozens of other commissions for major fashion and beauty houses. He is closely associated with fresh, luminous compositions built around citrus, sea notes, and white flowers such as jasmine, tuberose, neroli, and orange blossom, reflecting the Mediterranean and Andalusian scents of his childhood. Alongside his corporate work, he also founded his own personal-scent brand, Mizensir, which began as a line of scented candles in Geneva and later expanded into fragrances.

Morillas's contribution to the industry has been repeatedly recognized, including the Prix François Coty in 2003 and the Fragrance Foundation's inaugural Lifetime Achievement Award, along with lifetime-achievement-style honors from the German and Austrian Fragrance Foundations.