Technical Abstract: Historically, the call to conserve crop wild relatives has been driven by habitat degradation fueled by exponential population growth. Today, we have a clarion call for action, as historic impetuses are compounded by the forecast of global climate change. In the United States efforts have been moving forward to conserve the crop wild relatives’ native or naturalized in our own back yard. Before a national strategy can be organized, a comprehensive catalogue needs to be developed of CWR, which provides a starting point to prioritize efforts. This article describes how a preliminary inventory was developed. The preliminary inventory has over 2600 taxa. Over 364 taxa are useful for breeding 64 different crops. The most important genus is Helianthus, used to breed sunflower. Other genera that are CWR to domesticated crops, with over 10 or more native taxa, include Frageria, Lupinus, Prunus, Ribes, Rubus, Vaccinium and Vitis. CWR genera of domesticates that have limited representation in ex situ collections include Gossypium, Lactuca, Prunus, Ribes (gooseberry), Saccharum, Vaccinium (cranberry), Tripsacum and Zizania. The remainder of the list includes wild species related to crops used for medicinal, restoration and ornamental purposes. Many of these crops may be species not even domesticated, or have little or no current breeding efforts. The paper concludes by discussing the next steps needed to establish a national strategy to conserve crop wild relatives in the United States.