I have just started reading the book Augmentative and Alternative Communication: Engagement and Participation by Erna Alant. The book looks at supporting both AAC users and communication partners in developing both engagement and participation in dialogue. Participation refers to the frequency and nature of participation and includes many of the things that we commonly target when planning AAC interventions. Engagement is about the level of enjoyment experienced in interactions, the types of topics discussed, and the level of emotional resonance between the partners. Interventions using this framework include enhancing awareness and understanding in the AAC user of his own/her own interests, actions and feelings as well as enhancing the user's understanding of an interest in his/her communication partners. I'm looking forward to digging further in to this book!