Police chiefs remain concerned about the number of officers on the streets despite beating recruitment targets.
Despite recruiting success, the force needs even more officers
Thames Valley Police now boasts 4,124 full-time officers, a number that tops the 4,117 target set for 2004/5 by the police authority.
But that still leaves the force with just one officer for every 509 people living across the region.
The force's bosses say that is one of the lowest police officer to population ratios in the country.
The high cost of living in the Thames Valley and the attraction of higher pay in London have been blamed for ongoing difficulties in attracting more officers to the area.
While Sally Hannon, chair of the Thames Valley Police Authority, said she was "extremely pleased" with numbers reaching an all-time high, she added: "As a force we still have one of the lowest officer to population ratios, which is something we are always trying to improve."
A spokesman for the force's personnel department said: "We are working with our partners to deliver a visible presence, provide reassurance and tackle identified problems.
"We are committed to maintaining and improving officer numbers to ensure that residents and businesses within the Thames Valley receive best value and a high-quality policing service."
The force reached 4,000 officers for the first time in its history six months ago.
The level of police support staff has also risen to a force high, with 2,865 now employed.