A member of the Incorporated Society of London Fashion Designers (IncSoc), his style has been described as reflecting Parisian chic.

[5] Through trial and error, Cavanagh rose to become supervisor of Molyneux's London branch, before becoming his personal assistant in Paris, where he learned how the haute couture business worked.

[6] His first collection was greeted enthusiastically by the fashion reviewer of The Times, who said: "He used some of the best fabrics to be found on both sides of the Channel, with a minimum of seams and maximum play with the grain of the materials themselves".

[8] Although he had only been in business for a year, members of the English aristocracy ordered his dresses to wear for the Coronation celebrations, such as the gold brocade gown worn by Lady Cornwallis (née Esme d'Beaumont (1901–1969)), wife of Baron Cornwallis.

[8] He designed clothes appropriate to the lifestyles of his predominantly British and American clientele, such as cocktail and evening dresses, and tailored suits.

[14] As fashion became more youth-focused in the 1960s, Cavanagh attempted to redefine his business by moving into ready-to-wear, but this was not a success and he retired in 1972.