Bioluminescence is a striking phenomenon that is ubiquitous throughout the world’s oceans. Here we bring together the findings of in situ observations of bioluminescence in the upper ocean (<300 m depth) taken over several decades. We describe the distribution and diel variability of mechanically stimulated bioluminescence within the upper ocean, as well as its relationships with other environmental parameters. As dinoflagellates are often the dominant source of stimulated bioluminescence in the upper ocean we review current knowledge regarding the bioluminescence of these organisms including its potential ecological function. Modelling and prediction of the bioluminescent field has previously had only limited success, especially over timescales greater than a few days. We suggest that the potential exists to improve the forecasting of upper ocean bioluminescence potential on longer, seasonal, timescales by utilising and improving methods to model dinoflagellates.