Lek breeding is a mating system wherein aggregated males produce sexual displays for visiting females, who then select mates based on the quality of those displays. Even though bats display the widest range of mating behaviours of all mammalian Orders, lek breeding is disproportionally rare with only one confirmed lek-breeding species. This rarity is an anomaly, as bats possess all of the necessary prerequisites for lek evolution. Over the course of my PhD I have confirmed the use of lek breeding in a second species – the endangered Lesser Short-tailed Bat (Mystacina tuberculata) – using a myriad of techniques, including spatial analyses, video analyses, passive integrated transponder tags, and radio-telemetry. During the breeding season males establish night roosts in tree cavities and sing to attract passing females, who visit these ‘singing roosts’ to mate with the resident males. Spatial logistic regressions indicate singing roosts are clustered around large communal roosts used by females, providing evidence of a “resource-based lek” – i.e. males aggregating near resources required by females to increase female-encounter rates. Additionally, transponder records at singing roosts show that multiple males ‘share’ singing duties, a potentially unique behaviour amongst both bats and lekking species. I have also used male song characteristics, combined with morphometrics and genetic analyses to determine factors important in female selection of mates. I use my work on M. tuberculata to suggest that similar resource-based leks may be relatively common in bats due to life history characteristics shared by many temperate species that promote lek-like behaviour.