The Head of Department should be involved in timetabling to make the timetabler's job easier, as the subject leader understands the curriculum design and often has solutions to challenges. Involving the HOD prevents surprises and allows them to respond to questions. The HOD needs to understand staffing requirements, demand versus supply, and how to combine classes efficiently. Tasks for the HOD include analyzing staffing needs, determining how year groups can be combined, and completing staffing forms to show how subjects can be timetabled.