This thesis was written to celebrate and encourage the preservation of the American diner. The diner is a uniquely American cultural and architectural icon that will soon be lost without the intervention of historic preservation. Current diner preservation and restoration is typically performed by amateurs and enthusiasts who lack formal preservation education or training, which demonstrates a clear need for professional preservation assistance. As the diner regains a second wind in popularity, the need for formalized preservation strategies for diners will become apparent, and perhaps spark a movement in diner preservation. This thesis will examine the architectural and social histories of the diner, its need for historic preservation, and existing diners that have dealt with preservation in different ways.