This special issue covers recent advances in modeling, management and policies aimed at conserving groundwater or guiding transition strategies in the Ogallala Aquifer region. Topics include irrigation water-use efficiency, economic policies and analysis for groundwater conservation, crop response to water-saving strategies, water reduction programs, groundwater depletion forecasting, and the effects of a changing climate on groundwater supply and crop production. This issue is a repository of scientific methods and results from the Ogallala Coordinated Agricultural Project (CAP) team sponsored by USDA’s National Institute of Food and Agriculture, along with scientific contributions from others who are also researching the management of groundwater and crop production systems in the region. The results and methods published in this issue can may translate to or have relevance for groundwater conservation in other aquifer regions experiencing agricultural-related groundwater depletion.