Hamesse is said to have been Paul Hankar’s favourite trainee. His talent and business acumen led him to open an architectural and interior design studio, together with his brothers Georges and Léon, fairly early on in his career. This enterprise, which would enjoy great success in its time, was influenced by their father, Adolphe Hamesse, a fairly well-known landscape painter. The artistic environment he created would have a major impact on his sons. Their studio would go on to specialise in commercial developments and frontages following an initial large commission from the Cohn-Donnay store on the Rue Neuve/Nieuwstraat.