David Reibstein, Marketing Professor at Wharton, gives us his take on how digital is shaking up the marketing model. First of all, it's opening us up to new markets and putting a lot of control in the hands of consumers. That means it's no longer just companies talking at people—it's a multi-way conversation. As a result, he suggests we rethink how decisions are made in agencies. Senior players who've been doing this a long time may need to call on newer team members to inform big decisions.