Drs Willem Jan Hoogsteder (b. 1959) studied art history at Utrecht University and the Courtauld Institute of Art in London, and obtained his doctoral degree in 1987. He wrote his doctoral thesis on the painting collection of Frederick and Elizabeth, King and Queen of Bohemia.

The love for art was invested in him by his father and grandfather, who were both collectors.

Willem Jan Hoogsteder has been the owner-director of Hoogsteder & Hoogsteder art-dealers since 1989 and founded the Hoogsteder Museum Foundation in 2013. Both are situated at Lange Vijverberg 15 in The Hague.

Willem Jan Hoogsteder is Curator & Vice President of the Museum Bredius, The Hague and is the longest serving Board Member of the Utrecht Corps Museum. He is Old Master paintings expert on Tussen Kunst en Kitsch TV show and co-founder of Festival Masterly The Hague.

In 2019 Willem Jan Hoogsteder was awarded the Medal of Merit in Silver of the Red Cross. Two years later he was appointed Officer of the Order of Orange-Nassau. He was decorated with the Honorary Cross of the Order of the House of Orange in 2024. That same year he was created Officer of the Most Excellent Order of the British Empire.

Drs. Emilie den Tonkelaar (b. 1984) joined the team in 2009.
She studied art history at Leiden University and completed her research masters there in 2008 with a thesis on seventeenth-century artist Willem van Swanenburgh. She completed internships at Boston’s Museum of Fine Arts, Kunsthandel Laurentius in Middelburg and Staatliche Kunstsammlungen Dresden. In 2019 Emilie den Tonkelaar made world news headlines by discovering a famous oil sketch by Peter Paul Rubens. She is one of the paintings experts on Tussen Kunst en Kitsch TV show.

Daphne Martens, MA (b.1997) joined the team in 2024 as Art Historical Assistant & Provenance Researcher.
She studied art history and museology in Utrecht and Amsterdam. She completed the masters Curating Art and Cultures in 2023 with a thesis about Johannes Vermeer. Previously she worked as Assistant Curator & Project Manager at the Mauritshuis in The Hague, where she researched the still life paintings in the collection, organised symposia, edited publications and contributed to diverse exhibitions.