The exclusion of improperly obtained evidence is often discussed in relation to criminal proceedings but not civil proceedings, where concerns about wrongdoing of state actors and deprivation of liberty are not usually present. This thesis takes as its starting points (a) that it is sometimes assumed or claimed that there is no ability to exclude improperly obtained evidence in civil proceedings and (b) that some commentators consider that there should be no ability to exclude such evidence in civil proceedings. Contrary to (b), this thesis argues that recognition of powers enabling exclusion in civil proceedings is justifiable with reference to a version of the integrity principle (combined with the protective principle, where it applies). Contrary to (a), this thesis demonstrates that the jurisdictions under discussion (England and Wales, Aotearoa New Zealand and Australia) have recognised and/or developed powers enabling the exclusion of improperly obtained evidence in civil proceedings. This thesis argues that (to greater or lesser extents depending on the jurisdiction), recognition or development of the ability to exclude has occurred because of crossover from criminal procedure, ideas of abuse of process that relate to inherent power of the court (and can be explained with reference to an integrity principle), commitments to human rights and associated discourse. This thesis concludes with a proposal for further development of the jurisdiction-specific powers enabling exclusion. In summary, the proposal involves structuring the power to exclude by adopting a presumption of non-admission for evidence which has been obtained unlawfully and suggesting factors that should be taken into account when considering whether the presumption has been rebutted.