Changes to the libraries which include free Wi-Fi, new online services and extra events are due to be rolled out over the coming months.
The changes part a new deal agreed by Harrow Borough Council for John Laing Integrated Services Ltd to deliver library services from September.
The firm will run services in both Harrow and Ealing for the next five years.
New additions to libraries to during the coming months include the introduction of free Wi-Fi, new virtual library management system, and the chance for community groups to use buildings for events.
The merger of the Civic Centre Library with Gayton Library from August 25 will also be part of the plans.