Bird vocalisation research has principally focused on songs, whereas the study of unlearned calls has not been given proper attention. To understand the principles of Zebra Finch, and avian, vocal communication, a thorough comprehension of call usage is necessary. Zebra Finches emit thousands of calls daily. However, the exact number of call types, their functions and their inter-individual interaction patterns are not fully described and understood. This lack of knowledge mainly derives from the absence of appropriate tools for recording vocalizations individually. We developed and used miniaturised backpack microphones to record the total daily vocalisations of zebra finches pairs (ter Maat et al., 2014). This work had two primary aims: i) to quantify the calling behaviour ii) to correlate the calling and the social behaviours of Zebra Finches’ pairs. We used synchronised video and audio recordings to correlate the birds’ behaviour with their vocalizations. Zebra Finch pairs are characterized by the presence of particular behaviours, such as clumping and allopreening. We compared vocal and social aspects of the behaviour of already formed pairs and birds that had not previously met before. We described their call repertoire and found that it is similar among birds. Through quantitative analysis of the timing of calls of the two pair members, we discovered that these are used in bidirectional communication: pairs established precise patterns of alternated calling. Thus, we are able to show that there is a choice in answering certain specific call types with other specific calls with individual-specific precision. The quantitative description of calling behaviour will allow us to describe and further elucidate the role of different regions of the brain involved in vocal communication. Furthermore the different degree of uncertainty of the response, a “call me maybe” effect, can depend on the motivation of the individual and thus have important repercussions on mate choice studies.