Stretto—the technique of using a fugue subject in counterpoint with itself, beginning at different time points—occurs prevalently in fugues by J. S. Bach and other baroque composers. This study investigates the formal function of stretto using a corpus analysis of Bach’s use of stretto in the forty-eight fugues of the Well-Tempered Clavier. It documents details regarding each instance of stretto within the corpus and explores connections between these data using graphs and statistical tests, generally as well as in investigation of three specific hypotheses. The conclusion, density, and quantity hypotheses predict that there will be more stretto passages, time-intervals between onsets of adjacent entries in stretto passages will become smaller, and there will be more entries per stretto passage towards the end of the composition. The results do not provide strong evidence supporting any of these hypotheses, and they directly contradict the expectations of the density hypothesis
