A special class of scheduling problems is studied in this paper, named Hybrid Flowshop, n jobs have to be performed in a shop and each of them has the same routing (so this is a flowshop). A job consists in k different operations. A set of machines are able to perform each operation and this set is called a stage. So when a job consists in two operations, there are two stages in the shop. After introducing the scheduling generalities, we define our preocupations and we propose a notation in order to identify precisely and rapidly a problem. Then a state of the art is proposed and presented in two parts. The first one is dedicated to the 2‐stage hybrid flowshops and the second to the general case of the k‐stage. Then a summary puts to the fore that many problems remain unsolved.
