Listed sites are selected after meeting a combination of criteria, including historical, economic, architectural, artistic, cultural, and social values.
[2] The commission considers areas, districts, places, buildings, structures, works of art, and other objects within the City of Chicago for nomination based solely on whether each meets two or more of the following criteria:[3] Once the commission has determined that a candidate meets at least two of the above criteria, the group may provide a preliminary landmark designation if the candidate "has a significant historic, community, architectural or aesthetic interest or value, the integrity of which is preserved in light of its location, design, setting, materials, workmanship, and ability to express such historic, community, architectural or aesthetic interest or value.
"[4] In Chicago, the historic preservation movement initially sought to ensure the survival of individual buildings of special significance.
[5] However, the movement has evolved to include districts and neighborhoods and even encompasses distinctive areas of the natural environment.
All of those and a number of other districts, sites, buildings, structures, and objects worthy of preservation have been listed on the National Register of Historic Places.