This book focuses on new experimental and theoretical advances concerning the role of strange and heavy-flavour quarks in high-energy heavy-ion collisions and in astrophysical phenomena. The topics covered include * Strangeness and heavy-quark production in nuclear collisions and hadronic interactions, * Hadron resonances in the strongly-coupled partonic and hadronic medium, * Bulk matter phenomena associated with strange and heavy quarks, * QCD phase structure, * Collectivity in small systems, * Strangeness in astrophysics,* Open questions and new developments.