This, the first edition of the devotionary composed by Constanza de Castilla, granddaughter of Pedro I and prioress of the monastery of Santa Domingo el Real Madrid from approximately 1416 to 1465, is an important contribution to the small body of writing by medieval Spanish women available today.

Comprising a variety of prayers and liturgy offices in Spanish and Latin, the book provides moving evidence of the beliefs, experience, and expression of religious women in Spain of the later Middle Ages.