[Truncated abstract] This thesis examines the social and legal dynamics of support as it operated around women charged before the criminal courts in the eighteenth- and early nineteenth-century metropolis. It considers the nature and implications of the support made available to, or withheld from, female defendants by individuals to whom they were in some way connected. To this end, it explores the nuances of testimony offered by witnesses and defendants in an attempt to better understand the extent and effect of the support that could be negotiated by and from a range of groups, including family members, fellow household residents, neighbours and wider community members. How narratives were framed in either sympathetic or condemnatory terms was indicative of broader social attitudes and expectations regarding women and crime as well as of women's own relationships to households and neighbourhood. To the extent that this thesis aims to interrogate negotiations of support, it adopts legal narratives as a window through which to gain an insight into the social interactions and mediation of interpersonal relationships by eighteenth-century London women. The printed accounts of trials conducted at the Old Bailey and legal documents from the London and Middlesex Sessions records form the basis of the source material that contributed towards this study. These records provide contemporary narratives in which participants described their involvement in the legal system and articulated their relationships to events and to each other. As a result, they are invaluable for the wealth of qualitative detail they contain. These legal documents have also been complemented by other contemporary sources including newspaper reports and printed pamphlet literature. ... This thesis concludes first that neighbours and fellow household residents were usually in the strongest position to affect the outcome of criminal cases, either by offering assistance or disclosing incriminating information. The importance of household and neighbours rather than kin was closely tied to the domestic context in which many female crimes took place, and the 'insider knowledge' that was gained by living in close proximity to one another. However, if and when women retained links to family and kin who lived within travelling distance, they remained an important source of support. Secondly, the thesis identifies the detection and prosecution of crime as a gendered experience; contemporary social expectations about gender influenced both legal processes and the shaping of witness accounts. Thirdly, in its examination of local responses to female crime, the thesis supports the theory that a notable shift in sentiment towards female nature and legal culpability occurred during this period, which in turn affected the support offered to female defendants. Overall, the thesis demonstrates the paramount importance of witness testimony in articulating the circumstances surrounding female crimes, and the complex negotiations of interpersonal relationships which influenced how this evidence would be contextualised as supportive or not when it was delivered.