Guildford's Yvonne Arnaud Theatre will be lit in blue as part of a campaign from local charity Cherry Trees for World Autism Awareness Day.
In 2007, the United Nations declared 2 April as World Autism Awareness Day, aimed at raising international awareness of autism.
The Empire State Building, Princes's Palace of Monaco, Niagara Falls, Trafalgar Square, Orlando Eye and The Great Buddha are amongst the thousands of landmarks that will be lit blue for the event.
In Guildford, Cherry Trees is leading a blue procession, meeting at the March Hare from 5PM on Sunday and beginning at 6:10PM when the Mayor of Guildford, Councillor Gordon Jackson, will turn on the lights to illuminate Guildford Castle in blue.
The Yvonne Arnaud Theatre will be lit in blue as part of the campaign as will others buildings in the town centre, while shops will show their support with blue window displays.