Political power can take many forms, from the top-down model of the Roman Empire, to operating in the democratic politics of today, to the possibilities offered by new technologies for more horizontal power structures in the future.

Matthew Sweet is joined on a stage at the Hay Festival by historian Tom Holland, whose new translation of Suetonius? Lives of the Caesars examines Roman power politics from the inside; Guto Harri, who saw the inside workings of power as Downing Street Director of Communications; Adam Greenfield, whose book Lifehouse looks at local networks of mutual aid that have emerged in response to climate crisis; and political philosopher Sophie Scott-Brown - whose book The Radical Fifties: Activist Politics in Cold War Britain is out in July.

Producer: Luke Mulhall