The minimum age of a police community support officer is to be raised from 16 to 18, the home secretary has said.
Community support officers will get 20 discretionary powers
Jacqui Smith said the change would be implemented from 1 December and had the support of the Association of Chief Police Officers.
She said the role was a "demanding task which requires both mature and highly capable individuals".
In August Thames Valley Police defended its decision to employ two 16-year-old community support officers.
The pair would be allowed to confiscate alcohol consumed in public, despite being too young to drink, and have the authority to direct traffic even though they cannot drive.
Thames Valley Police said on Friday the pair would continue to be employed after the latest age change comes into effect as their employment met previous requirements.
Twelve other forces said they did not employ under 18s.
Ms Smith announced other changes, including setting 20 standard powers across England and Wales and 20 at a chief's discretion.
There are 16,000 police community support officers in England and Wales, supplementing the 140,500 police officers in 43 forces.
A Home Office spokeswoman said it did not have a record of the ages of support officers, but had changed the age to standardise practice across forces.
The role of police community support officer was created in 2002 and the Home Office said it would now introduce a code of practice for forces.
Ms Smith said: "Police Community Support Officers are massively popular with local people and they are making a difference in local communities.
"PCSOs have got a massive, important role to play in helping to build the confidence of local people."
The 20 standard powers include confiscating alcohol in public places, issuing fixed penalty notices for anti-social behaviour and seizing drugs.
The additional 20 powers which will be allocated at the discretion of the chief constable include detaining suspects, issuing fixed penalty notices for disorder, and searching people suspected of carrying dangerous items.
Acpo has also commissioned a project - from the National Policing Improvement Agency - to improve standardisation of equipment, uniforms, training and career development.
The Acpo chief constable in charge of neighbourhood policing, Matt Baggott, said the support officers were a "vital role within neighbourhood policing teams".
"They work alongside police officers and partners to respond to local concerns and to provide the levels of visibility and accessibility which the public tell us they want.