College Terrace Library was built in 1936 and is housed in a building of approximately 4,860 square feet. Designed by local architect, Charles K. Sumner, the building also houses a day care center operated by Palo Alto Community Child Care. In April 2008, the City Council approved reclassification of the building from a Category 4 to a Category 2 structure in the City's historical building inventory.

After a year long closure for upgrades and earthquake retrofitting, the College Terrace Library re-opened on Tuesday, November 9, 2010.

College Terrace houses about 13,000 books for adults and children. While there are no meeting rooms available and parking is limited, there is free Wi-Fi, printing, and computers available for use.

Downtown Library recently underwent an extensive renovation as the first phase of building projects approved through Measure N.

This library branch holds about 15,000 books, mainly for adults, with a small children's section. It features one meeting room (seating up to 4), free Wi-Fi, printing and computers, and both street and lot parking.

Mitchell Park Library was opened to the public in 1958.

The library is approximately 41,000 square feet and is part of a new 56,000 square foot joint library & community center facility. Mitchell Park and Rinconada branches were the result of a bond issue of $700,000 approved in 1956.

In 1974-75, Federal Revenue Sharing funds were obtained to expand the facilities floor space by 70 percent to its current size.

Mitchell Park Library is the largest of the branches with the first floor housing mostly children's and teen materials. The first floor includes study rooms and a dedicated teen room. The second floor houses more than 50,000 items for adults, has a Vintage Media Lab by appointment, two additional study rooms, and two terraces. There is a parking lot, printing, computers, and free Wi-Fi.

Rinconada Library was formerly called the Main Library.

In 1956, a $700,000 bond issue was approved for the construction of two new library facilities, the Main Library, and the Mitchell Park Library. The Main Library, designed by Edward Durell Stone, designer of the United States Exhibit Hall at the Brussels World's Fair and the Stanford University Hospital, opened in 1958.

The original building was 26,313 square feet, including a 5,000 square foot basement. This library had the largest collection in the system, including the principal reference collection and the archives of the Palo Alto Historical Association.

It served primarily adults and teens and had a very small children’s collection. The original building had possessed 25,000 square feet of space.

In 1982-84, the building was renovated and 2,200 sq. ft. of staff work space was added.

The Main Library closed for major renovation on April 30, 2013. The upgrade was funded with proceeds of the $76 million bond measure (Measure N) passed by Palo Alto voters in November 2008. The improvements to Main, renamed Rinconada Library, include the addition of approximately 4,000 square feet to the current 26,300 square foot library. A new wing with restrooms and a 100-person community meeting room was added. Four small group study rooms were also added to the building. The interior of the existing library was reconfigured and totally upgraded with the addition of air conditioning. All the improvements were made with consideration for the historic nature of the existing building.

Rinconada Library houses approximately 45,000 items and has a dedicated teen room. Printing, computers, free Wi-Fi, and parking in a lot are available.