The present invention provides a child seat (1) comprising a seat back (3), a headrest (4) which is moveable relative to the seat back (3), and a removable harness which may be installed for use in securing an occupant to the seat (1), wherein the headrest (4) is coupled to the seat back (3) such that the headrest (4) may undergo a first extent of movement relative to the seat back (3) when the harness is installed and may only undergo a second further extent of movement relative to the seat back (3) when the harness is removed. In this regard, only when the harness is removed from an operative position, namely one where it is installed such that it can be used to restrain a child, can the headrest (4) undergo its second further extent of movement relative to the seat back (3). This ensures that the headrest (4) is not inappropriately positioned for the group of child being restrained thereby.