The Royal College of Surgeons in Ireland (RCSI) disposed of part of its antiquarian library by sale and disposal through a process which began in 2011 and was completed in 2015. This paper outlines the reasons that led to this decision, its execution and the benefits to the library and institution deriving from it. The disposal of library collections, especially by sale, is a sensitive topic within the library profession and academic research communities. At the time it was made the decision provoked reactions ranging from outrage to unequivocal support. Now, seven years on, the short, medium and long-term outcomes of the decision are evident. Specifically, this paper will provide context for the decision making; describe the evidence based approach taken, and the due diligence process followed; outline the business case presented to the governing body of the College and the importance of getting agreement from the outset that funds from the sale of books would be ring fenced by the College for the purpose of preserving and exploiting the RCSI archives and remaining books; discuss the mechanics and logistics of getting auction ready; the transformation and development of what were severely neglected unique and distinct archives into the RCSI Heritage Collections as a brand, and the provision of associated services to support the visibility, findability and accessibility of the collections. The paper will also reflect on and illustrate the value of the newly branded Heritage Collections to institutional priorities such as equality and diversity, reputation enhancement, and public outreach. It also seeks to provoke reflection and discussion on professional issues concerning behaviour, ethics and standards, which were encountered on this journey of divestment and transformation.