Moulaert studied at the Royal Conservatory of his hometown from 1890 to 1898 with Gustave Léon Huberti (music theory, theoretical harmony) , Joseph Dupont (harmony), Arthur De Greef (piano) and Edgar Tinel (counterpoint and fugue). He then became a teacher at his university for harmony, for organ (1903) and from 1927 to 1940 a teacher of counterpoint.

He was also a repetitor and pianist at the Royal Monnaie Theatre from 1898 to 1912. In 1903, he obtained an honourable mention in the Prix de Rome with his cantata La Chanson d'Halewyn on a text by L. Solvay. Moulaert was already working in secondary music education before 1913 as a teacher at the Sint-Joost-ten-Node Municipal Music School and from 1913 to 1938 as director of the Sint-Gillis Municipal Music School. It can be considered the apotheosis of his pedagogical work that he was teacher of harmony and composition at the Queen Elisabeth Music Chapel from 1939 to 1943.

In 1955, he became a member of the Académie royale des sciences, des lettres et des beaux-arts de Belgique. In 1958, he was awarded the Belgian government's five-year prize for his overall œuvre.

Initially impressionistic in style, his work was later modern in structure. For orchestra, he wrote in a Bartókian manner, liking to use variation techniques within the strict forms.

[Source: Wikipedia]