[2][3] Guilard received the "Agrégation de Sciences Physiques" Degree in 1966 and a PhD in 1971 from the University of Burgundy.

[2][5] Guilard was Scientific Director of the Department of Chemistry at the French Ministry of Education, Technology and Research,[2][4] and then Managing Director for the partnership of local authorities in the Partnership Branch of the Centre National de la Recherche Scientifique, CNRS.

[2][4] Guilard founded two companies, Chematech[2][6][7] and PorphyChem[2][7][8] which produce tetraazamacrocycles, porphyrins, phthalocyanines and related compounds, respectively, for use in research, industrial applications[9][10] and health care.

Guilard holds 23 patents, including a technique for decontamination of radioactive elements from wastewater,[2][12] a process for removing lead from drinking water[2][13][14] and a carbon monoxide sensor.

[2][15] He has published more than 475 articles in peer-reviewed journals[2][16][17] and has co-edited several influential book series including The Porphyrin Handbook,[2][18] the Handbook of Porphyrin Science,[2][19] the World Scientific Series on Chemistry, Energy and the Environment,[2][20] and the World Scientific Series: From Biomaterials Towards Medical Devices.