A total ban on smoking at Guy's and St Thomas' hospitals has come into force.
Patients and visitors can no longer smoke anywhere on hospital premises – or at any of the community clinics run by the same NHS foundation trust.
Smoking e-cigarettes is also not permitted. Staff have not been allowed to smoke on Guy's and St Thomas' premises since January 2014.
"We are asking everyone who uses our services or visits our hospitals or community buildings to play their part in helping us to create a healthier environment for everyone," said Guy's and St Thomas' chief executive Ron Kerr.
"We know that patients recover more quickly after surgery or illness if they do not smoke. Our Stop Smoking Service supports patients while they are in our care, if they need help to stop smoking."
Smoking inside the hospital buildings was banned a decade ago.