The phrase "invaluable experience" means an extremely valuable or precious learning opportunity or knowledge gained from a particular event or situation. Full definition
During that time he gained invaluable experience in the discharge of the responsibilities that a local authority has towards children and adults who live within the area. (1cor.com)
This is an excellent opportunity for someone to gain invaluable experience in a fast paced, rapidly growing business environment. (careerbuilder.com)
This has provided her with invaluable experience of the insurance industry, the important issues for the industry, risk management and assessment and the very real commercial issues associated with claims handling. (beale-law.com)