 Arenal's achievements were extraordinary in a largely traditional Spain, focusing her work on those marginalised in society.She wrote not only extensively on the state of prisons for both men and women, but also on the role of women in society in works such as "La Mujer del Porvenir" (1869), The education of women, The current state of women in Spain, The work of women, The woman of the house (1883) and domestic service.It is this work which made her known as the founder of the feminist movement in Spain.