A new hospital inspection regime for England is getting under way, with the chief inspector promising to "expose poor and mediocre" care.
The Care Quality Commission agreed to overhaul its inspections following the Stafford Hospital scandal.
Inspectors will visit Croydon Health Services NHS Trust, in south London, later - the first of 18 inspections taking place before the end of 2013.
Mike Richards, the new chief inspector of hospitals, is leading the process.
The inspection teams are larger and more specialised than before - about 30 people are taking part in the Croydon visit, including a surgeon, senior nurses, a student nurse and members of the public.
There will also be a public meeting held in Croydon on Tuesday evening - something that will be happening during the other inspections too.
Another crucial difference is that the inspections will focus on the "whole patient experience".
Each inspection will cover eight key services areas: A&E; medical care; surgery; critical care; maternity; paediatrics; end-of-life care and outpatients.
The inspections will be a mixture of announced and unannounced visits and they will include inspections in the evenings and at weekends.
That contrasts with the previous inspections which were grouped around essential standards so hospitals would find themselves inspected for issues such as nutrition and infection control rather than the entire system.
Sir Mike said: "These inspections are designed to provide people with a clear picture of the quality of the services in their local hospital, exposing poor or mediocre care as well as highlighting areas of good and excellent care.
"We know there is too much variation in quality in the NHS - these new in-depth inspections will allow us to get a much more detailed picture of care in hospitals than ever before."
The launch comes amid heightened focus on the performance and regulation of hospitals.
The public inquiry into the poor care at Stafford Hospital, published in February, identified failings in the way hospitals are monitored.
Weaknesses were once again highlighted in July when the government's Keogh Review led to 11 hospitals being placed in special measures. Only two of them were facing regulatory action from the CQC, suggesting problems were slipping under the radar.
Health Minister Norman Lamb said: "Our priority is to make sure that people get better care. That's why we asked the CQC to appoint a new Chief Inspector of Hospitals to shine a spotlight on quality and drive up standards across the board."
The programme of inspections continues on Thursday when inspectors go into Airedale NHS Foundation Trust followed by inspections at Taunton and Somerset NHS Foundation Trust and The Royal Wolverhampton NHS Trust next week.
By the end of 2015 the CQC aims to have inspected all acute hospitals.
Results will be published about a month after each inspection.