Three series of lectures were given at the 32nd Probability Summer School in Saint-Flour (July 7-24, 2002), by the Professors Pitman, Tsirelson and Werner. ThecoursesofProfessorsTsirelson("Scalinglimit, noise, stability")andWerner ("Random planar curves and Schramm-Loewner evolutions") have been p- lished in a previous issue ofLectures Notes in Mathematics (volume 1840). This volume contains the course "Combinatorial stochastic processes" of Professor...