Techniques for creating policies for use in policy-based management of quality of service treatments of network data traffic flows are described. Policies are defined based on information about types of flows generated by an application and quality of service functions that are available in the network. Application information is received that defines flows generated by an application, including points where the application generates the traffic flows. QoS information is received that defines one of more quality of service treatments that the network device may apply to data processed by the network device. Based on the information, processing policies that associate the flows with the QoS treatments are determined. Mappings of the application information to the QoS treatments, which may be used to generate the quality of service value when the application program generates flows, are created and stored. Thus, the policies are informed both by application expertise and network expertise.