In one of his first papers, written jointly with Jan Kratochvíl in 1989, Jirka Matoušek initiated the systematic study of combinatorial and algorithmic properties of various classes of string graphs, that is, intersection graphs of continuous arcs (strings) in the plane. In a posthumously published essay (CRM Series, 2015), he addressed similar questions. During the quarter-century that elapsed between these works, he regularly returned and richly contributed to this subject and, more generally, to geometric graph theory. In this talk, we recall some of Jirka's most significant achievements in this field, and mention a few recent results.