Technical Abstract: Global warming and climate change have been widely accepted as facts. The changing environments pose serious challenges to global agriculture and place unprecedented pressures on the sustainability of horticulture industry. Adapting horticulture to future conditions is essential to meet the need of growing population and increasing demand for fruits, vegetables, and other horticultural products. Forecasts show that warming over the next several decades will take place irrespective of any action taken today. Therefore the development of horticultural crops that can cope with heat, cold, drought and other climate extremes brought by a warming planet may well be the single most important step we can take to adapt to the changes we face today and in the future. However breeding a new variety takes time, often about 10 years. Our ability to breed these new varieties is undermined by the rapid loss of the biological basis of horticulture – the genetic diversity of plants, which is in turn accelerated by climate changes. In addition, it is estimated that more than 20% of all cultivated lands around the world contain levels of salts high enough to cause stress on crop plants, a situation worsened by global warming. There is an urgent need to mitigate these abiotic stresses through improvement of horticultural crops. This enormous and difficult task requires tremendous efforts from multiple disciplines. Stress physiology research identifies mechanism of stress tolerance and provides approach, method, and traits for screening stress-resistant genotypes. Molecular biology and genomic studies lead to a better understanding of the structural organization and functional properties of genetic variation for stress-related traits, allow gene-based selection through identification of molecular markers and high-throughput genotyping techniques, and increase the genepool available including new sources of stress-tolerant traits or transgenes. Plant breeders translate these findings into stress-tolerant crop varieties by using all tools available that include germplasm screening, marker-assisted selection, plant transformation, and conventional breeding methods. Vegetable Breeding and Stress Physiology working groups of the American Society for Horticultural Sciences co-sponsored a colloquium “Improvement of Horticultural Crops for Abiotic Stress Tolerance” at the society’s 2010 annual conference in Palm Desert, California. In the colloquium, leading scientists in this field introduced the need, significance, and benefit of stress tolerance in fruits, vegetables, and ornamental crops; discussed the current status and challenges of research in stress physiology, molecular biology, genomics, plant transformation, germplasm enhancement, and crop breeding for resistance to abiotic stresses; and identified opportunities, strategies, and priorities for future progress. With its summer heat and dry weather, Palm Desert was the perfect place to discuss this topic.