The International Board for Plant Genetic Resources (IBPGR) promote a set of morphological characters considered to be the minimum number for the description of crop germ plasm collections. The format and style of these IBPGR minimum descriptors are typical across numerous crop and species genera. However, no research publications have reviewed the relative usefulness of individual descriptors, nor indeed if additional descriptors should be included into the "minimum descriptor list".A diverse collection of 1,379 spring sown barleys were evaluated for the 12 IBPGR "minimum" descriptors, an "additional" 9 morphological descriptors of similar type of the minimum descriptors, and a contrasting group of 3 hordein and 3 leaf esterase biochemical markers. Multivariate analyses were performed on combinations of the "minimum", "additional" and biochemical markers to reveal detailed associations amongst these various descriptors. The IBPGR minimum descriptor list for barley was shown to be inadequate in descriminating between accessions, and a revised list is proposed.