This plaque was installed in 2006, in the wall of the official residence of the Mayor of Amsterdam.
The 17th century monumental house was owned by Paulus Godin, who was on the board of the Westindische Compagnie, a company that made money with slave trading.

Full translation of the Dutch text on the plaque:

As long as the memory lives, the suffering was not for nothing
In this house, built in 1672, lived and worked until 1690 Paulus Godin (board member of the West-Indische Compagnie and general manager of the Society of Suriname).
In these functions he was responsible for the buying and selling of Africans who were made to slaves, and were transported to the Caribbean, formerly the West Indies.
Today, Amsterdam has many inhabitants of whom these Africans are the ancestors.
Slave trading and slavery are crimes against humanity.
(The text of this plaque has been made on the initiative of the Council of Amsterdam, on August 23, 2004, the day which has been made the International Day for the Remembrance of the Slave Trade and its Abolition by UNESCO).

Address:
Herengracht 502, Amsterdam