The term “Intent” is used in network management to designate the specification of goals or outcomes, without specifying how to achieve them. Ideally, intent should be specified in a natural language (e.g., English), but it must then be transformed into a representation that can be interpreted by the network devices. The term “Autonomic Network” is used to describe a network that assumes many management functions “on its own”. Such networks are well-suited to being “intent-driven”. This thesis provides a comprehensive definition of Intent, in the form of a set of Intent Objectives. A set of Intent examples (expressed in English) is then presented, chosen to reflect intents from three distinct network environments (Carrier networks, Data Center networks, and Enterprise networks), and all of the Intent Objectives. Transformations of the examples into the Autonomic System Specification Language (ASSL) are given. ASSL was designed for the specification and verification of autonomic systems. We show that, in spite of being designed for autonomic systems, ASSL is capable of expressing network intents. The expressiveness of ASSL is evaluated by demonstrating that it can cover almost all of the Intent Objectives, for the three network environments. We conclude with discussion of the expressiveness of ASSL, with respect to each of the Intent Objectives, and the ways in which the current ASSL development environment could be improved.