A&E departments are on course to meet waiting time targets, a report says.
The government wants waits cut to less than four hours
About 96% of patients in England are being seen and treated within four hours, according to emergency care tsar Sir George Alberti.
He also said the NHS was on target to ensure all A&E patients are seen within the target time - set down as part of the NHS Plan - by the end of the year.
Health Secretary John Reid vowed the government would not be complacent about ensuring standards are met.
And he added more work was needed "to provide even better and quicker services for patients".
But Liberal Democrat health spokesman Paul Burstow said the report was "utterly complacent".
"Overworked staff and frustrated patients will not recognise this perfect picture of a shiny happy A&E."
Earlier this month, a National Audit Office report also predicted the health service was on target.
The 96% figure represents a significant improvement from the end of 2002 when less than 80% of patients were dealt with within four hours.
'Envy of the world'
The achievements have come at a time when A&E departments are seeing more patients than ever.
More than 16m people are seen in A&E units each year - up from 13m in 1992.
Sir George, national clinical director for emergency care, said the days where people were forced to spend whole days or nights waiting in A&E units were over.
"The progress made so far is a tribute to all those working in the service."
However, he acknowledged improvements needed to be made treating the elderly and people with mental health problems - as highlighted by the NAO report.
He also said there were still not enough doctors and it would be eight years before the desired numbers were achieved.
His report, Transforming Emergency Care in England, said waiting times had fallen as patients were seen first by people who could treat them and improvements had been made in discharging people.
Ambulance crews were also encouraged not to always bring patients to A&E if a GP referral or walk-in clinic was more appropriate.
The majority of NHS trusts had also set up assessment units, wards which meant patients could receive quick treatment from acute physicians.
Prime Minister Tony Blair said it was a "remarkable improvement".
"Congratulations to everybody who has been involved in this.
"We are beyond the levels of treatment they have in the United
States, Canada and around the world."
But shadow health secretary Andrew Lansley said the four-hour target only served some patients.
"People working in casualty departments have now got a grip of how they can deliver important services, but they want now to move to a quality mentality, where patients are addressed on the basis of their clinical priority but...wherever possible when you see patients arriving you treat them straight away."
Martin Shalley, president of the British Association of Emergency Medicine, praised the introduction of targets which had "focused clinicians' and managers' minds".
"This has led to improvements in staff morale and great improvements in the throughput of patients in emergency departments."