A 16-year-old boy has been charged with the murder a man who died after a "disturbance" at a house, police have said.
The 18-year-old man was found with serious injuries after police were called to an address in The Avenue in Watford just after 21:50 BST on Tuesday.
He died in hospital a short time later.
The boy, who cannot be named for legal reasons, is due to appear before magistrates in Hatfield later.
Hertfordshire Police said it was believed to be "an isolated incident".