Acta Crystallographica Section E: Structure Reports Online is the IUCr highly popular open-access structural journal. It provides a simple and easily accessible publication mechanism for the growing number of inorganic, metal-organic and organic crystal structure determinations. The electronic submission, validation, refereeing and publication facilities of the journal ensure very rapid and high-quality publication, whilst key indicators and validation reports provide measures of structural reliability. In 2009, the journal published over 4000 structures. The average publication time is less than one month.