Henk N.W. Lekkerkerker (1946) studied chemistry at Utrecht University (the Netherlands) and obtained his doctorate at the University of Calgary (Canada) in 1971. He then moved to Brussels initially as a postdoctoral fellow at the Université Libre de Bruxelles (Belgium) and subsequently became a professor of Theoretical Physical Chemistry at the Vrije Universiteit Brussel. From 1985 till 2011, he has been a professor of Physical Chemistry at the Van 't Hoff Laboratory, Utrecht University, and from 2006-2011 he was also Academy Professor of the Royal Netherlands Academy of Arts and Sciences. He received for his work on the phase behaviour of colloidal dispersions  the following awards: Bourke Award, Royal Society of Chemistry (1993), Onsager Medal, Norwegian University of Science and Technology Trondheim(1999), Solvay Award, European Colloid and Interface Society (2003), Bakhuis Roozeboom Gold Medal, Royal Dutch Academy of Sciences (2003), Liquid Matter Prize .European Physical Society (2008), Lennard Jones Award, Statistical Mechanics and Thermodynamics Group of the Royal Society of Chemistry (2011), Overbeek Gold medal, European Colloid and Interface Society (2018).  Remco Tuinier (1971) studied food science at Wageningen University (the Netherlands) and performed his PhD work at the NIZO food research institute and Wageningen University on colloid–polymer mixtures. Subsequently, he worked as a postdoctoral fellow at the Van 't Hoff Laboratory, Utrecht University and in 2001 became a staff member at the Forschungszentrum Jülich, Germany. From 2008 to 2015, he worked at DSM Research, Geleen, the Netherlands, as a senior and principal scientist of colloids and interfaces. Since 2013, he has been a part-time professor at Utrecht University. In 2015, he became a full professor of physical chemistry at Eindhoven University of Technology, the Netherlands. Remco Tuinier is a member of the IACIS council, chairman of the board of the Overbeek foundation and Editorial Advisory Board member of The Journal of Chemical Physics.  Mark Vis (1988) studied chemistry at Utrecht University (the Netherlands). He obtained his PhD at the Van 't Hoff Laboratory, Utrecht University in 2015 on the thermodynamics of incompatible aqueous polymer mixtures, also known as water-in-water emulsions. In 2016, he joined the Physical Chemistry group at Eindhoven University of Technology as a postdoc and became an assistant professor in 2019. His main research interests are colloid–polymer and polymer–polymer mixtures, with a particular focus on interfaces, synchrotron scattering, and aqueous systems.

• 1. Introduction.- 2. Depletion Interaction.- 3. Phase transitions of hard sphere–depletant mixtures — the basics.- 4. Phase separation and long-lived metastable states in colloid–polymer mixtures.- 5. The interface in demixed colloid–polymer dispersions.- 6. Phase behaviour of colloidal binary hard sphere mixtures.- 7. Phase behaviour of colloidal hard spheres mixed with hard rod-like colloids.- 8. Phase behaviour of colloidal rods with depletants.- 9. Phase behaviour of colloidal platelet–depletant mixtures.- 10. Phase behaviour of colloidal cubes mixed with depletants.

Henk N.W. Lekkerkerker (1946) studied chemistry at Utrecht University (the Netherlands) and obtained his doctorate at the University of Calgary (Canada) in 1971. He then moved to Brussels initially as a postdoctoral fellow at the Université Libre de Bruxelles (Belgium) and subsequently became a professor of Theoretical Physical Chemistry at the Vrije Universiteit Brussel. From 1985 till 2011, he has been a professor of Physical Chemistry at the Van 't Hoff Laboratory, Utrecht University, and from 2006-2011 he was also Academy Professor of the Royal Netherlands Academy of Arts and Sciences. He received for his work on the phase behaviour of colloidal dispersions  the following awards: Bourke Award, Royal Society of Chemistry (1993), Onsager Medal, Norwegian University of Science and Technology Trondheim(1999), Solvay Award, European Colloid and Interface Society (2003), Bakhuis Roozeboom Gold Medal, Royal Dutch Academy of Sciences (2003), Liquid Matter Prize .European Physical Society (2008), Lennard Jones Award, Statistical Mechanics and Thermodynamics Group of the Royal Society of Chemistry (2011), Overbeek Gold medal, European Colloid and Interface Society (2018).  Remco Tuinier (1971) studied food science at Wageningen University (the Netherlands) and performed his PhD work at the NIZO food research institute and Wageningen University on colloid–polymer mixtures. Subsequently, he worked as a postdoctoral fellow at the Van 't Hoff Laboratory, Utrecht University and in 2001 became a staff member at the Forschungszentrum Jülich, Germany. From 2008 to 2015, he worked at DSM Research, Geleen, the Netherlands, as a senior and principal scientist of colloids and interfaces. Since 2013, he has been a part-time professor at Utrecht University. In 2015, he became a full professor of physical chemistry at Eindhoven University of Technology, the Netherlands. Remco Tuinier is a member of the IACIS council, chairman of the board of the Overbeek foundation and Editorial Advisory Board member of The Journal of Chemical Physics.  Mark Vis (1988) studied chemistry at Utrecht University (the Netherlands). He obtained his PhD at the Van 't Hoff Laboratory, Utrecht University in 2015 on the thermodynamics of incompatible aqueous polymer mixtures, also known as water-in-water emulsions. In 2016, he joined the Physical Chemistry group at Eindhoven University of Technology as a postdoc and became an assistant professor in 2019. His main research interests are colloid–polymer and polymer–polymer mixtures, with a particular focus on interfaces, synchrotron scattering, and aqueous systems.

• 1. Introduction.- 2. Depletion Interaction.- 3. Phase transitions of hard sphere–depletant mixtures — the basics.- 4. Phase separation and long-lived metastable states in colloid–polymer mixtures.- 5. The interface in demixed colloid–polymer dispersions.- 6. Phase behaviour of colloidal binary hard sphere mixtures.- 7. Phase behaviour of colloidal hard spheres mixed with hard rod-like colloids.- 8. Phase behaviour of colloidal rods with depletants.- 9. Phase behaviour of colloidal platelet–depletant mixtures.- 10. Phase behaviour of colloidal cubes mixed with depletants.

Henk N.W. Lekkerkerker (1946) studied chemistry at Utrecht University (the Netherlands) and obtained his doctorate at the University of Calgary (Canada) in 1971. He then moved to Brussels initially as a postdoctoral fellow at the Université Libre de Bruxelles (Belgium) and subsequently became a professor of Theoretical Physical Chemistry at the Vrije Universiteit Brussel. From 1985 till 2011, he has been a professor of Physical Chemistry at the Van 't Hoff Laboratory, Utrecht University, and from 2006-2011 he was also Academy Professor of the Royal Netherlands Academy of Arts and Sciences. He received for his work on the phase behaviour of colloidal dispersions  the following awards: Bourke Award, Royal Society of Chemistry (1993), Onsager Medal, Norwegian University of Science and Technology Trondheim(1999), Solvay Award, European Colloid and Interface Society (2003), Bakhuis Roozeboom Gold Medal, Royal Dutch Academy of Sciences (2003), Liquid Matter Prize .European Physical Society (2008), Lennard Jones Award, Statistical Mechanics and Thermodynamics Group of the Royal Society of Chemistry (2011), Overbeek Gold medal, European Colloid and Interface Society (2018).  Remco Tuinier (1971) studied food science at Wageningen University (the Netherlands) and performed his PhD work at the NIZO food research institute and Wageningen University on colloid–polymer mixtures. Subsequently, he worked as a postdoctoral fellow at the Van 't Hoff Laboratory, Utrecht University and in 2001 became a staff member at the Forschungszentrum Jülich, Germany. From 2008 to 2015, he worked at DSM Research, Geleen, the Netherlands, as a senior and principal scientist of colloids and interfaces. Since 2013, he has been a part-time professor at Utrecht University. In 2015, he became a full professor of physical chemistry at Eindhoven University of Technology, the Netherlands. Remco Tuinier is a member of the IACIS council, chairman of the board of the Overbeek foundation and Editorial Advisory Board member of The Journal of Chemical Physics.  Mark Vis (1988) studied chemistry at Utrecht University (the Netherlands). He obtained his PhD at the Van 't Hoff Laboratory, Utrecht University in 2015 on the thermodynamics of incompatible aqueous polymer mixtures, also known as water-in-water emulsions. In 2016, he joined the Physical Chemistry group at Eindhoven University of Technology as a postdoc and became an assistant professor in 2019. His main research interests are colloid–polymer and polymer–polymer mixtures, with a particular focus on interfaces, synchrotron scattering, and aqueous systems.

• 1. Introduction.- 2. Depletion Interaction.- 3. Phase transitions of hard sphere–depletant mixtures — the basics.- 4. Phase separation and long-lived metastable states in colloid–polymer mixtures.- 5. The interface in demixed colloid–polymer dispersions.- 6. Phase behaviour of colloidal binary hard sphere mixtures.- 7. Phase behaviour of colloidal hard spheres mixed with hard rod-like colloids.- 8. Phase behaviour of colloidal rods with depletants.- 9. Phase behaviour of colloidal platelet–depletant mixtures.- 10. Phase behaviour of colloidal cubes mixed with depletants.