In 1931 Lacasse founded Galerie l'Equipe, focus of a movement comprising also literature and drama, and an open platform to all young artists seeking recognition. During that time, Lacasse revisited his memories of the stone quarries of Tournai and returned to the possibilities of exploring colour through fragmentation, luminosity and composition. Amongst the frequent visitors of l'Equipe during 1937 was the then figurative painter Serge Poliakoff, who borrowed much from Lacasse to deliver his first abstract painting at the gallery in 1938.

The works of Lacasse are included in the following museums: Musée d'art moderne de la Ville de Paris, Musée national d'art Moderne, Centre Pompidou, Paris, Musée des Beaux-Arts, Brussels, Musée de Tournai, Tournai, Tel Aviv Museum of Art, Tel Aviv, Eilat Museum, Eilat, Carnegie Institute, Pittsburgh, National Gallery of Victoria, Melbourne, Musée des Arts Décoratifs, Paris.