This study examined similarities & differences in cases defined by the coroner as suicide & open verdicts & the implications of open verdicts for suicide research. All cases of open & suicide verdicts recorded in the Newcastle (UK) Coroner’s Court in the period 1985-1994 were compared on demographic and medical parameters. Open & suicide verdicts had many similarities, differing only in some respects, of which logistic regression identified the most significant to be a suicide note, method used, & age. Open verdicts should be included in all suicide research after excluding cases in which suicide was unlikely. Objective criteria are needed to facilitate comparison between different studies. (16 refs.)