In many regions of the world, flooding poses a significant threat to the survival of plants. Inundation is harmful to almost all higher plants, including crops. The vast majority of crop plants are extremely sensitive to flooding, resulting in dramatic yield losses each year. This chapter provides a summary of scientific approaches to the development of flood-resistant crops. The majority of research has been conducted on maize, barley, and soybeans. Anatomical adaptations, such as aerenchyma formation, the formation of a barrier against radial oxygen loss, and the growth of adventitious roots, hold the most promise for enhancing crop flooding tolerance. Metabolic adaptations may also improve waterlogging tolerance, but additional research is required in this area. Quantitative trait locus (QTL) analysis or genome-wide association (GWA) studies in combination with easily measurable tolerance traits are viable approaches for future research. In these experiments, the use of flooding-tolerant relatives or ancestral cultivars of the crop of interest could increase the likelihood of discovering useful tolerance traits for use in breeding.