A cabinet reshuffle is when the prime minister moves around the members of his or her cabinet, the group of people who have really important jobs in the government. It usually happens when a cabinet minister resigns, needs to be replaced, or when the prime minister wants to signal a change in policy or priorities. It can be very minor or it could involve a lot of changes, with ministers moving departments and creating new roles.
Prime Ministers reshuffle their cabinet to change the team or refresh the top team, which can help keep their party and government looking fresh. They can also use it to reward loyal ministers by promoting them or to remove those who are not doing a good job of running their department. Reshuffles are often more significant when there is a new prime minister from the same political party taking office between general elections.
Other reasons for a reshuffle include to give a chance to new MPs to be part of the cabinet, and to make sure that different groups are represented in the cabinet. The prime minister might also want to give a big boost to his or her favourite policy area.
Reshuffles are most common in parliamentary systems, where the ministers are drawn from the legislature. But they can happen in other systems, too, especially if the executive and legislative branches of government are separate. They are also less common in systems where the executive needs to have the approval of a legislative body before making appointments.