Patients in England will no longer be guaranteed a GP appointment within 48 hours under a scaling back of NHS targets.
Instead, doctors will be allowed to prioritise patients, affecting up to 189m consultations a year.
Changes will also be made to the four-hour A&E and 18-week hospital treatment waiting time targets.
Health Secretary Andrew Lansley announced the moves, which represent a major shift in policy from Labour.
The previous government used targets as a way of driving through improvement.
But in the lead up to the election the Tories claimed it was time to move away from the target culture and instead focus more on the quality of treatment.
Mr Lansley said: "I want to free the NHS from bureaucracy and targets that have no clinical justification and move to an NHS which measures its performance on patient outcomes.
"Doctors will be free to focus on the outcomes that matter - providing quality patient care."
GPs have long complained the 48-hour target can put the most seriously-ill patients at risk as appointments get clogged up with people who do not need immediate access.
Dr Laurence Buckman, of the British Medical Association, said: "We would welcome the scrapping of this target as it will give GPs greater flexibility to organise their appointment booking system in a way that best suits their local patient population."
But the Patients Association said it was concerned about the speed of the changes.
Spokeswoman Katherine Murphy said while moving away from targets was the "right idea", it was important to have something in place first to stop a "free for all".
The changes in the other areas are seen as much less radical.
The hospital waiting target move is more relevant to managers than patients.
The guidance makes it clear hospitals will still be expected to see patients in 18 weeks, but they will not have to prove it to local managers, meaning less paper-work.
Meanwhile, the threshold for seeing A&E patients within four hours will be lowered from 98% of patients to 95%.
The move is just the start of what will be a complete change in how performance is managed in emergency departments.
A new measurement is likely to be introduced, which is likely to include an element of waiting alongside other factors such as access to scans.
The idea, again, is to focus on quality rather than just what is deemed to be the rather blunt instrument of waiting time.
In the guidance issued to the NHS in England, Mr Lansley also makes it clear that these changes can help save money on management - 46% in the coming years.
However, that still equates to a modest saving for the health service as management accounts for less than 2% of its budget.