Ever since I was a boy in Siberia, I knew of Maestro Rostropovich as a legendary cellist and conductor whose generous personality inspires everyone. After the deaths of master violinist Yehudi Menuhin and beloved conductor Leonard Bernstein, it's Mstislav Rostropovich, at 77, who is the world ambassador of classical music — the last of that generation who can communicate music's wonder. He's like my grandfather. He's my hero. And I call him my angel, because he supports me as a mentor and we have more than a musical friendship.

Growing up the Soviet city of Baku, he always had music in his family; both parents were musicians. Then when he was 16 he won a place at the Moscow Conservatory, where his teachers included the great composers Sergei Prokofiev and Dmitri Shostakovich. They and many others wrote works especially for him. Musically, Rostropovich is the link for younger generations to those geniuses and others like Benjamin Britten, all of whom he knew well. And he really understands what music means. He has taught me not to force my personality into a work, but instead to try to touch the spirit of the composer; then the audience can connect with the music's universal emotions. He knows also that sometimes music isn't just about the sound — there's a message behind it, like the hopeful patriotism in Shostakovich's "Leningrad" Symphony — and that those messages can apply to the world's troubles today.

He believes that if you do something good it will not only help in that instance but serve as an example of how every human can make a difference. That's why he gives so much time in his incredibly hectic schedule to projects like his vaccination program for children in Russia and elsewhere. Since 2000, his charitable foundation has provided vaccinations for nearly 2 million children across the Russian Federation, protecting them against mumps, measles, rubella and hepatitis B. His work with these kids symbolizes all that is great about the Russian soul. For that reason, Russians love him — everyone knows him. You go to a remote village, they know of him. He reaches far beyond the music world. He has had more impact on the lives of ordinary Russians than many politicians. I particularly admire the way the program implements education and infrastructure, so the work can continue in that place without him. It epitomizes Rostropovich's musical values — cultural enrichment, continuity and improvement. Generations have been touched by this miraculous spirit, and will continue to be touched long after he has gone. — By Maxim Vengerov, star classical violinist and protégé of Rostropovich.