Major physiological changes occur in the maternal cardiovascular system during pregnancy. In women with pre-existing or previously undiagnosed cardiac disease, these changes may precipitate cardiac decompensation. The number of women with heart disease embarking on a pregnancy is increasing. Heart disease is the commonest cause of maternal death in the UK where all maternal deaths are critically reviewed. In approximately half of the women who died from cardiac disease in the UK, suboptimal care was identified. In the Netherlands, the maternal mortality rate from cardiac disease (2004–2006) was 3 per 100 000 maternities. Multidisciplinary teams working and co-location of clinical services are critically important to ensure the best care possible for pregnant women with cardiac conditions (Figure 28.1).