The Gilbertine order was unusual in that it was founded for both men and women who lived in adjacent enclosures. The order had its origins in the Lincolnshire village of Sempringham where St Gilbert founded the order in the 1130s. The canons followed the rule of St Augustine and the nuns the rule of St Benedict. The history of the order has been extensively researched by Brian Golding from its foundation until the beginning of the fourteenth century. However, there has been little substantial research on the order in the period from the fourteenth century until its dissolution in 1539. This dissertation continues the work carried out by Golding and examines the later years of the order’s history and its dissolution. The main themes of this work are the recruitment of men and women into the order during the fifteenth and sixteenth centuries, the spiritual lives of the nuns, the impact of the dissolution on the lives of the men and women of the order, and their careers after the dissolution. The study will show that in common with other religious orders there was a decline in the popularity of the Gilbertines in the later Middle Ages, and also a relaxation of the rules the nuns followed. In the period after the dissolution, the thesis will demonstrate that the social and economic position of former Gilbertine canons was much better than that of former nuns.