The discussion between Snowball, group chairman and chief executive at the Omnicom agency, and Al-Qassab, chief brand and marketing officer at the telecoms business, took place on the 34th floor of the imposing BT Tower in central London.
The full story will appear in the first issue of the new Campaign, out on Monday 11 September, with both written and film versions available on our website next week. You can see a sneak peek of The Conversation right now.