The increasing rates of intervention in childbirth are an issue for women, their families, health professionals, and society across much of the Western World. This study is a response to these increasing rates of intervention, as reflected in the research question: 'What is shaping the practice of health professionals and the understanding of the public in relation to increasing intervention in childbirth?' The participants in the study were nine health professionals: midwives and obstetricians, who were interviewed individually, and thirty-three members of the public who took part in six focus groups. The research was carried out under the umbrella of critical hermeneutics, and the particular approach used was that of critical interpretation as formulated by Hans Kogler. This approach enabled a hermeneutical thematic analysis of that which is shaped (worldviews) and a critical structural analysis (discursive orders, social practices, relationships of power and structures of domination) of the shaping and shapers of practice and understanding. The research process facilitated by critical interpretation in identifying and describing the shaping and shapers of practice and understanding adds an important dimension to the statistical picture of increasing intervention that is of concern, both to health professionals and the public. The research revealed that the everyday world and its associated processes of socialisation in the 21st century - in particular pain, choice, and technology - shape the practice of health professionals and the understanding of the public in relation to increasing intervention. The study's findings were supported by the revelation that many of the social and cultural values, such as convenience, ease, and control, that underpin Western society in the 21st century, correlate with what intervention has to offer, which results in intervention being increasingly sought after and utilised. This milieu of intervention, which increasingly surrounds childbirth, is shown to be calling into question those things that have traditionally been at the heart of childbirth: the ability of the woman to birth and the clinical skills of the health professional. This research provides insight and awareness of those things that are shaping understanding and practice and birth itself and creating a milieu in which intervention is increasingly normalised.