Working on natural substances, part of the research of the LCSNSA (Chemistry Laboratory of Natural Substances and Food Sciences) is devoted to volatile compounds from plants. The objectives are multiples and can be summarized in four points: (1) Research of bioactive molecules (2) Chemotaxonomic studies (3) Applications in perfume industry (4) Plant-insect interactions Each of these four points will be discussed and illustrated by one or several examples of research projects conducted in the LCSNSA. The first two points exclusively concern volatile compounds generated by essential oils extracted from endemic or indigenous plants of Reunion, Mauritius, Madagascar and Comoros islands. The two last points are dedicated to volatiles found in the airspace (headspace) surrounding above-ground plant parts (flowers and fruits). This communication will also present a selection of sampling methods for volatile compounds that range from conventional, inexpensive, solvent-free, quick sampling methods to innovative method; as well as an overview of detection and identification methods of volatiles including GC-FID and GC-MS.