As hunter-fisher-gatherers, the lives of Mesolithic humans in Britain would have revolved, to a great extent, around the daily encounters and interactions with animals that were necessary for the provision of nutrients for survival. Traditional narratives of human-animal relations have viewed animals through an economic lens, interpreting their significance in terms of the nutritional or material resources they provided Mesolithic humans. However, more recent studies argue human-animal relations in the past should instead be considered as developing through their daily interactions and engagements with each other, in which animals have the potential to play an active role in shaping human understanding. In such narratives, animals are no longer a resource: instead, they are potential agents.This thesis uses zooarchaeological data from four Early Mesolithic faunal assemblages from Southern Britain to characterise the appearance, habits and behaviours of the species and individuals within each assemblages. These are used to consider the specific encounters humans had at each site, and the particular understandings humans formed as a result. Ultimately, if human treatment of animal remains was guided by an understanding developed through encounter and engagements, it is vital these experiences are understood. Furthermore, negotiations of relationships developed through encounters are traced through processes of hunting, killing, butchery, consumption, and deposition, exploring how these understandings and relationships are manifest in the material record.