Remember the old, safe world where you could design a new product, give a technical specification to some developers, then sit back and wait for results? That world has gone. Digital technology — in the hands of your customers and your employees and, increasingly, instrumenting the physical world — both creates and constrains new business model possibilities. Few individuals have the breadth of knowledge and few firms have all the resources they need to master this new reality, driving the need for co-creation, whether it's with internal teams, vendors, or your customers. This brief gives some examples of firms that are learning how.