The Port Arthur Public Library is charged with acquiring, organizing, and providing access to a wide variety of information and materials to help fulfill the intellectual, educational, social, and recreational needs of the entire community. The Library upholds the principles of intellectual freedom and the public's right to know by providing people of all ages, races, creeds, and physical conditions with access to information and materials reflecting all points of view.

The Library designs and provides services, programs and facilities to satisfy the varied information needs of its community and is responsible for their orderly operation and maintenance. It promotes the use of these resources by keeping the community informed of their availability. The Library is the primary agent of lifelong learning in the community. Its staff aims to carry out this mission with input from the community it serves, recognizing the need to change as the community changes.