Since 1989 he has been working in the Ministry of Environment. He has held and served in several key posts including Director General for Nature Conservation and Principal Secretary of Environment. Didier was chairperson of the National Planning Authority, Waste and Landscape management Agency and the National Parks Committee. Furthermore he served on several boards of national importance such as the Seychelles Tourism Board, the Island Development Company.
He was the Founding Chairman of the Non-government Organisation called Plant Conservation Action Group; a botanical association, which seeks to promote the conservation and protection of the endemic and indigenous flora of Seychelles.
He played an instrumental role in implementing the Seychelles debt swap for conservation and climate adaptation and the Seychelles Marine Spatial Plan.
On the international arena he has represented Seychelles in many sustainable development, biodiversity and land degradation related negotiations and fora in particular the UNCBD, UNCCD and RIO+ 20. He chaired the Nairobi Convention COP 8 meeting.