Peter Redhead will join the board as non-executive director on November 1. Redhead runs an executive coaching company, Redhead Coaching.
He was was previously a managing director with investment bank JP Morgan in London, running the European Equity Research Group and before that, the Equity Research Group for Asia Pacific.
The company said it thanked Herbert for his contribution over the last four years.
Alexon Group operates brands including Ann Harvey, Eastex and Alex & Co.