In 1984, Hamilton created an installation for an Arts Council group exhibition titled Four Rooms. The invitation led him to re-engage with the genre of the interior and to recall the confident, starry eyed, Utopianism of his 1950s collage Just what is it that makes todays homes so different, so appealing? Though artists in the post-war moment had dreamed of a better future, he found the spirit of the 1980s to be one of contrasting depression, and determined that his room would be inspired by the bleak, disinterested, seedily clinical style of the establishment institution.
Treatment room had overtones of DHSS Labour exchanges and NHS waiting rooms. Beyond a screen was a slab table on which one might imagine a patient. Hanging above was a monitor repeating footage from the Conservative Party Election Broadcast from 1983, showing Margaret Thatcher in a classical interior. Thatcher had spoken about stability; Hamilton silenced her, recognising that the power of the broadcast was as much in the image of Conservatism as in her actual words.
The installation dealt with the workings of power through surveillance (the monitor reminding the viewer of CCTV cameras in public spaces) and indoctrination (the patient cured by the image of the leader). Hamilton ended his text accompanying Treatment room by asking: Is the vision of Mrs Thatcher patronising a victim of the health service part of that future we once thought so bright?