In 1964, he formed an architectural firm in Buenos Aires with six associates (Flora Manteola, Ignacio Petchersky, Javier Sánchez Gómez, Josefina Santos, and Justo Solsona).

"One of his most handsome recent projects is the Laguna Garzón Bridge, a circular road deck and pedestrian walkway whose design allows an eco-friendly crossing over the environmentally sensitive 4,448-acre lagoon on the nation's coast.

'"[20] Noting the "astonishing" number of major projects he "left scattered across that island and its adjacent territories", most memorably the controversial supertall, super-skinny Midtown condo building (its width-to-height ratio is 1:16)[21] at 432 Park Avenue, the design critic Ian Volner observed, "Anyone so frantically prolific was bound to run into the clothesline of public opinion at some point."

Ticking off Viñoly's most problem-plagued buildings—his 20 Fenchurch Street tower in London and his Vdara resort complex in Las Vegas, whose glazed façades turned reflected sunlight into a blistering "death ray"—Volner suggested that his "attraction to ideas like transparency and simplicity trumped other, more quotidian considerations".

Fred A. Bernstein, writing in The New York Times, noted Viñoly's avoidance of a "signature style" beyond his allegiance to modernism and his "penchant for enclosing large spaces under glass, creating luminous interiors".

[22] In another Times article, the architect David Rockwell, who worked with him on several projects, most notably on a proposal for the rebuilding of the World Trade Center, recalled the team's vision of the twin towers reborn as a structure that spiraled defiantly skyward, "a filigreed weave of steel and air [that] would transform the center for trade to one of civics and culture"—a testimonial, Rockwell recalled, to "Rafael's love and belief in the power of beauty and culture.

"In an era when every 'starchitect' worth the name was chasing glamorous museum commissions, Viñoly was just as happy to be recognized for his work with laboratories, hospitals and universities," wrote Jebb.

"The architects he most admired included, historically, Andrea Palladio, and in the modern era Oscar Niemeyer, creator of Brasília, and the minimalist master Mies van der Rohe, whose Seagram Building (completed 1958) was Viñoly's favorite in New York.

[26] The Uruguayan architect "immediately received the kind of attention normally reserved for our soccer players who emigrated to Europe to play in the English Premier, Spanish, or Italian Leagues," he wrote.

"Our shared connection with Viñoly was an additional, beneficial layer to our rapport, and once again I found myself inspired by the possibilities of stepping beyond cultural background, country of birth, and language, solely based on the work," wrote Kripper.

"Viñoly was a bridge and an open door to the fact that ... a person with a clearly different name, with an accent included, could become an architect, an entrepreneur, a businessperson, and a founder of a company in the United States."

[27] Two of the skyscrapers designed by Viñoly, the Vdara in Las Vegas and 20 Fenchurch Street in London, have experienced sun reflectivity problems as a result of their concave curved glass exteriors, which act as cylindrical and spherical reflectors, respectively.

[28] In London, sunlight reflecting off 20 Fenchurch Street during the summer of 2013 melted parts on a parked Jaguar and scorched the carpet of a nearby barber shop.

[31][32] A foot longer than a typical concert grand and hosting no crossed strings, the Maene-Viñoly piano was completed in 2022 and premiered at the Verbier Festival played by Kirill Gerstein.

[33] In the months after Viñoly's death, the instrument was hosted at the Philadelphia Orchestra[34] and featured at a Carnegie Hall concert in November of 2023 where it was played by Jonathan Biss.