Although Eugène Gaillard was educated in jurisprudence, he did not long practise law. Instead he became a sculptor, craftsman and furniture designer and in this last capacity Eugène Gaillard was indeed a leading Art nouveau artist of his day.
Interiors, furnishings and textiles Gaillard designed were also marketed by Siegfried Bing through his Maison Art Nouveau. At the 1900 Paris Exposition, the art dealer had his own pavilion, "Art Nouveau Bing", featuring six model rooms, each of which simulated a living environment. All objects shown, including furniture, textiles and crafts objects, were designed by three artists: Edward Colonna, Georges de Feure und Eugène Gaillard. Bing was the first to apply the principle of "creating an ambience" to his exhibitions, a development that matched the trend towards the total work of art. The natural and lively interrelationship of things was to be clearly recognisable and each object was to be presented in the place for which it was intended to be used.
Until 1914 Eugène Gaillard designed exquisitely elegant furniture in the Art nouveau style. His approach to design and motifs reveals floral inspiration yet was not intended to imitate nature, as he explained in a 1906 essay entitled "À Propos du Mobilier".
In 1901 Eugène Gaillard co-founded the Société des Artistes Décorateurs, exhibiting his designs at their Salon shows.