Roberto Stern took over H. Stern in the 1990s and turned the Brazilian jeweler around

Hans Stern, a German-Jewish immigrant who fled Nazi Germany, founded H. Stern in Brazil in 1945 and built it around the country's colored gemstones. His son Roberto studied economics, worked in finance and advertising, and joined the company in the mailroom after studying at the Gemological Institute of America.

In 1991 Hans asked Roberto to oversee the workshops and stores in São Paulo, the company's most lucrative market. Roberto redesigned the collections — less is more — and the São Paulo shops began outselling the other Brazilian stores. He then revamped the rest of the outlets and rebuilt manufacturing so one artisan did multiple tasks; a new collection that once took one to two years now took two months.

About eight years later Hans convened his four sons to choose a leader; given Roberto's success in turning the company around, they voted him into the top spot. By 2003 H. Stern had about 160 stores and estimated sales of $300–500 million, and Roberto was pushing the brand's internationalization.

From a mailroom start, Roberto oversaw 160 stores and an estimated $300M–$500M in sales; new collections went from 1–2 years to every two months.

Design-led, pared-down collections gave the brand a clear message.

Manufacturing reform (one artisan, multiple tasks) slashed collection lead times.

The family settled leadership by vote, avoiding the infighting that kills family firms.

Internationalization spread the repositioned brand beyond Brazil.

A successor can turn a family firm around by making the product itself the strategy — Roberto cut the collections to a clear brand message and rebuilt manufacturing around artisans.

H. Stern grew into one of the world's best-known Brazilian luxury names with stores from Paris to Tokyo. After Hans's death in 2007, Roberto continued as chief and the family kept ownership; the 1990s handover is cited as the moment the jeweler was modernized.