In April 1997 he started a consulting firm called Eldred Boonzaaier Consulting Engineers with himself being the only shareholder. In June 1998 Eldred Boonzaaier and Loyiso Dotwana merged their consulting engineering practices to form Boonzaaier Dotwana & Associates. In November 2000 Boonzaaier Dotwana and Associates merged with Fongoqa Skade Toyi and Associates to form ILISO.

Consulting at which time Eldred was appointed Financial Director for ILISO Consulting. Eldred is currently the Chief Operations Officer at NAKO ILISO and a member of the Executive Committee. Eldred has gained invaluable experience with the commercial, operational and strategic aspects of running a business in addition to the technical design aspects of engineering.

His experience includes structural design using various building material such as concrete, structural steel, timber, aluminium, masonry, composite materials. Experienced in Industrial, Office, Retail, Residential, Institutional, Sport, Educational and Health Facilities. Extensive experience in the design foundations on problem soils such as heaving clays, variable foundation conditions, collapsible soils etc. Eldred has also gained extensive experience as a Project Manager having been the Project Manager for the Eastern Cape Department of Roads and Public Works for the 4 phases of their Emergency Reconstruction Programme.