Yarra Plenty Regional Library Service, formerly Heidelberg Regional Library Service, was established in 1965 to provide library services to the City of Heidelberg and the Shires of Diamond Valley and Eltham. The City, (then Shire) of Whittlesea joined the service in 1976.

In 1995, following changes to the Local Government boundaries, the new municipalities of Banyule, Nillumbik and Whittlesea continued their support for the regional library service and Yarra Plenty was one of the first incorporated library regions established under the new Local Government Act.

The library service covers an area of 983 square kilometres and includes metropolitan, urban fringe and rural populations. It reaches a population of 290,000 of whom 145,000 are members.
It has a collection of 530,000 items, lends 3.7 million books and other items each year and employs equivalent to 100 full-time staff with a budget in 2002/2003 of more than $8 million.

Branch libraries are located at Diamond Valley, Eltham, Ivanhoe, Lalor, Rosanna, Thomastown, Watsonia and Mill Park. A Mobile Library provides service to areas without easy access to a branch library and a specially designed van visits housebound and institutionalised residents throughout the region.

Responsibility for the provision and management of the Library Service rests with the Regional Library Board, which comprises two representatives from each of the three member Councils.