Slie is the abbreviation for the Sierra Leone Institution of Engineers, a prestigious professional organization that brings together professional, graduate, and student engineers. Established in 1970 under an act of Parliament, the organization operates under the Professional Engineers Registration Council. The main purpose of Slie is to promote and advance the field of engineering in Sierra Leone.

Slie is committed to providing various services to its members, including professional development opportunities, publications on engineering topics, and organizing events and workshops. These initiatives serve to enhance the skills and knowledge of engineers, ensuring they stay updated with the latest advancements in the industry. One of Slie's recent activities was a Consultative Workshop held in Makeni to foster collaboration and exchange ideas among engineers.

Additionally, Slie has engaged in discussions with institutions such as UNOPS, the Road Maintenance Fund Administration, and the SL Maritime Administration to develop a new Continuing Professional Development (CPD) Framework. With its dedication to the engineering community and its efforts to facilitate professional growth, Slie serves as a vital resource for engineers in Sierra Leone