There are jobs favourable to biodiversity, which we call bio-jobs. These jobs are located in a small number ofsectors generally linked to natural resources: naturalist research, forestry sector, public works, water and wastemanagement, etc. In this article, we are interested in two economic policies favoring the development of thesebio- jobs. The government can support demand in sectors concentrating bio-jobs through public procurement, orshe can develop them through targeted exemptions. The most effective and relevant combination of theseinstruments is looked for via an original framework. We show that the action of the government is driven by thenature of the sectors and especially the level of an existing private demand. Then, the level of the wages plays amajor role in the government budget decision. We finally apply these recommendations to French data.