Before graduating from Womenswear Central Saint Martins College of Art and Design in 2015, Alexander Byun worked for a succession of companies such as Bottega Veneta, Chanel and Christian Dior. He shaped his aesthetic through refining the study of 3D shaping of his designs.

During his final year graduation Collection he received a fabric sponsorship from Christian Dior and decided to expand the collection. He shortly after went to work for Givenchy to the position of Womenswear Junior Designer Specialised in 3D. After leaving the house, he established AUGUSTUS BYUN.