An 'AAC system' refers to all the communication support technologies, modes, and strategies that an individual with CCN may use to communicate effectively with anyone, anywhere, at any time, for any reason. Ultimately, the individual with CCN chooses what to use, where, and with whom. An AAC system is comprised of communication support technologies, as well as strategies that make conversations flow more smoothly and help each partner in the interaction remain actively engaged. The goal of an AAC system is to support authentic interactions. Therefore, the development of AAC systems must also address each interactant's knowledge of how/when to use specific modes, methods, tools, and techniques to communicate with different people, in different contexts, for different purposes.