Westbrook, once a rural town, is an outlying suburb of Toowoomba where housing subdivisions have spread over Toowoomba's western boundary into the former Jondaryan Shire. Westbrook is on the road from Toowoomba to Pittsworth (the Gore Highway) and is 6 km south-west of central Toowoomba.

The Westbrook pastoral run was taken up by John 'Tinker' Campbell in 1841 (the property's stone homestead in Couper Road, built by later owners in 1867, is listed on the Queensland heritage register). In the late 1850s many of the best-watered parts of Westbrook's 44,500 ha were pre-emptively acquired by the owner, inhibiting prospects for closer-settlement. In the 1870s some of the hills and ridges on Westbrook were severed for use by selectors, and in 1898 some 10,000 acres were further resumed by the colonial authorities for closer-settlement purposes.

By the turn of the century Westbrook had two local primary schools, Bunkers Hill (1899) and Westbrook (1910-69). Better known, but best forgotten, was the Westbrook Training Centre, opened in 1900. A notorious youth detention facility, it was identified in the 1960s as a haven for sadistic warders and a training ground for future criminals. The centre continued for another 30 years, albeit with improved supervision, before eventually closing in 1994. It was among the institutions investigated as part of the 1998 Commission of Inquiry into Abuse of Children in Queensland Institutions (Forde Inquiry). From 1994 it operated as a low-security prison for male offenders before being closed in 2012 and split into parcels of land for sale for development in 2014. The various name changes were as follows:

yearinstitutional name
1900Westbrook Reformatory for Boys
1919Westbrook Farm Home for Boys
1966Westbrook Training Centre
1987Westbrook Youth Centre
1993Westbrook Youth Detention Centre
1994Darling Downs Correctional Centre
2012Closed

One of the few continuing features of Westbrook has been a general store, joined in recent years by a large tavern, two neighbourhood parks and local tradespeople.

Westbrook's census populations have been:

Census DatePopulation
1911753
1921474
1961387
20062288
20113287