Ciro Castelli joined the Laboratory of the Superintendency of the Uffizi Gallery in November 1966 a laboratory that merged into the Opificio delle Pietre Dure in 1975. He remained a permanent member of staff until his retirement in 2010.
Post-retirement, he has continued to work seamlessly for the OPD as a mentor for new generations of wooden painting restorers.
From 2010 to 2018, this was through a project funded by the Getty Foundation, the Getty Conservation Institute, and the Getty Museum; since 2018, he has served as a consultant for the Fondazione Opificio.
Throughout his long career, he has worked on the most significant masterpieces on wooden supports, devising innovative systems for painting conservation and combining bench-work with extensive educational and training activities.
In 2023, the Contrada di Valdimontone (Siena) awarded him a Gold Medal in recognition of his outstanding contribution to the safeguarding of historical and artistic heritage.