Institutionalisation has played a key role in Irish social policy, however there is still a lack of clarity regarding the relationship between the governing structures (government departments, medical and education regulators etc.) and those who ran the institutions, such as the Catholic convent institutions for ‘fallen’ women. Specifically a question remains as to the precise logic for transferring girls and women into these settings. This paper expands the debate by exploring the existence of Catholic Convent industries in Ireland through the lenses of spiritual eugenics in the early 20th Century. In contrast to Anglo‐American eugenic practices based on sterilisation and birth control, Latin eugenic practices accepted by the Catholic Church were based on removing women from temptation and may have produced a necessary commitment to long‐term closed institutions. The paper offers a brief description of the differences between eugenics aimed at biological fitness and the practices aimed at spiritual promotion.