Ward, who was previously the brand director, will continue her current responsibilities running the agency's Young's Brewery, Liberal Democrats and Swan Hellenic accounts, but will work to sell Banc's branding, advertising and design proposition to existing and new clients.
The agency set up a direct marketing arm earlier this summer, and is also planning to introduce other services including brand internalisation and digital branding.
The chairman, Robert Bean, said: "Banc's obsession is providing clients with notoriety and consistency at every touch point. It's what every company in the world wants, few have and even fewer offer.
"It's a huge opportunity for us, and Emma has equal measures of charm and tenacity, a great combination for a new-business role. She is also a passionate believer in our unique proposition."
Ward added: "I'm looking forward to selling something I strongly believe in. The Banc way of working has had a profound effect on our existing pieces of business and I want to ensure that we spread the word."
Before joining Banc in 2000, Ward was an account director at Publicis, where she worked across various accounts including Muller Dairy, McVities, Diet Coke, Allied Bakeries and Ryvita.