Dimitri Shostakovich, too, was a central part of this group: "We organised the premieres here of a number of his symphonies," Hochhauser relates, showing me an autograph book laden with extraordinary signatures. "I once went with him to see West Side Story! I'm not sure he really enjoyed it, but he never left anything early, so he sat there quietly until the end. His English was not so good, so we managed to communicate in German. I remember thinking, 'I'm not big enough for this, taking Shostakovich to the theatre…'"
The challenges of organising tours for companies like the Mariinsky and the Bolshoi (who came to London last summer) never cease to evolve but, knowing the clients inside-out can only help: "Both of these companies are a joy to bring to London," Hochhauser declares.
"Not only do I know them so well, having worked with them for so many years, I also admire their arts - they are really brilliant performers and I feel very lucky that they feel the same way and like working with me.
"It's not entirely a year's work to put it on," she adds, "but it is a very big undertaking, and expensive, so one has to think very carefully and while trying to give people what they love, also try not always to bring the same thing. The inevitable Swan Lake does form the core of all the seasons - but I think, the way they dance, one can stand another performance of Swan Lake!"
The Mariinsky's Swan Lake can indeed be one of the wonders of the ballet world - even with its strange, happy ending. "That's Russia," Hochhauser twinkles.
The word is nevertheless filled with nostalgia. After Stalin's death in 1953, the Hochhausers encountered Igor Oistrakh, the violinist son of David Oistrakh, performing in London; they got to know him and managed to arrange a concert tour for his father in Britain the following year. "My husband, with great courage, jumped in," says Hochhauser.
So did she. "Of course it was terribly exciting to go to Russia in those first days. I went to a big hotel facing the Kremlin and I couldn't believe how run-down it was. One couldn't even buy a coffee, and shops were almost non-existent. That was quite difficult to take in. But it was fascinating and the people we were bringing over were more than fascinating: Oistrakh, Richter, Rostropovich - imagine such artists waiting to come to the west, as eager to see us as we were to see them! It was thrilling to hear them, meet them and forge really deep friendships with them. When things are difficult, you do get very close to people."
Things did sometimes become difficult, on many levels. Once the Hochhausers organised a tour to Japan for the BBC Symphony Orchestra and Pierre Boulez, who was conducting and had written a new work which was supposed to be premiered there.
"Having had quite a time persuading a small Japanese town that they did want Boulez's music and that it was a great honour to have the premiere, on the day we found the stage wasn't big enough for all the musicians!" They managed to salvage the situation: "In the end, they just repeated the concert from the night before, and we went and had a picnic, which was wonderful."
Much more painful, though, was a long period in which the Hochhausers found they were persona non grata in the USSR.
"We couldn't go to Russia for 16 years," Hochhauser says. "When that came to an end, with perestroika in 1992, we went straight back - and the first thing I did was to go and find Richter, to bring him here. He died only a few years later, in 1997, and I still miss him. I found it very difficult to listen to the piano for a long time afterwards."
The companies, too, have had their ups and downs: in particular, the Bolshoi Ballet faced a turbulent time following an acid attack on its then director, Sergei Filin, in 2013.
Despite the scandal, the company's visit to London last summer was a roaring success and Hochhauser is well placed to take a longer perspective on the company's resilience: "They dance on through everything."
Away from the office, Hochhauser has always maintained her fondness for Jewish traditions.
"I was brought up in a traditional house and I've kept the tradition going - I'd feel rather guilty about breaking a 5,000-6,000 year tradition," she smiles. "It has been a very big part of my life."
And her birthday celebration? A trip to the opera of course. "I do feel rather at home at Covent Garden!"
Approaching her tenth decade with such enviable aplomb, she, too, dances on through everything.
