[3] In 1970, the firm was relocated to offices in Four Elms Road, Cardiff, where the duo were then joined by a third partner, Bryan Alcock.
Associated Dairies later became the supermarket chain Asda, with the firm's work expanding to cover several towns and retail projects across the United Kingdom as a result.
Later known as the Atlantic Wharf development, Mathias, Holder and Alcock designed the project at a cost of £50 million.
Other clients included 3M, Sony and Hewlett Packard, with the firm active in the London Docklands, the Roath basin and Cardiff.
[1][3] In the late 1990s, the firm expanded its operations into Europe, establishing an architectural partnership in Munich, Germany, in 1999 and participating in multiple retail developments throughout the continent.
[5] Holder Mathis is registered in England and Wales as a private limited company, with architectural activities as its stated nature of business.