Defensive behaviours are a range of strategies that an organism employs to cope with threatening stimuli. In social animals like mice, threats can be in the form of aggressive conspecifics, competing for territory and resources for male mice, or unwanted social interactions, like sexual advances from unfamiliar males for female mice. These aversive situations can be de-escalated by the avoidance of the threat, displaying submissive postures or even by defensive attack. The ventrolateral subdivision of the ventromedial hypothalamus (VMHvl) has been shown to be essential for the expression of both avoidance and aggressive behaviours, and the activity of its neurons increase at the onset of these behaviours. However, it is not clear how these neurons interconnect to mediate the behavioural response, especially during avoidance of a social threat.We used in vivo electrophysiology to record from the VMHvl of male and female mice at the onset of escape from a social threat. We established a new circular behavioural arena where pairs of mice interact freely and display ethologically relavant social avoidance behaviours like high velocity chases and submissive upright postures. Using this paradigm, we have identified classes of single units that encoded different aspects of defensive behaviors. Importantly, our circular arena also allowed us to also measure defensive behaviors in sexually non-receptive females avoiding advances from unfamiliar males. Finally, we have used optrode stimulation to identify the connectivity of the recorded units in order to understand how the activity dynamics of the classes can lead to escape from a threat.