Even as the last survivors of the Holocaust age and pass away, their memories - and the memories of the millions who were murdered during this dark chapter in history - live on. In Europe, the victims of the Nazis are often commemorated with brass plaques, which are also feeling the effects of time. But the BBC tells us about one man, this week's Advocate and Ally of the Jewish people, who is cleaning and repairing these memorials to Holocaust victims:
In recent years, many towns in Central Europe, including Germany and Austria have introduced small brass plaques in the streets in memory of Jews and other victims of Nazi atrocities.
The plaques, an initiative by the German artist Gunter Demnig, have been placed outside the houses where they used to live.
There are 388 of them in the Austrian town of Salzburg.
Over the years, some have been damaged by wear and tear and winter weather - but now a 79-year-old man has started to renovate them.