Personalized augmentative and alternative communication (AAC) intervention refers to an approach in which intervention is tailored to the individual's needs and skills, the needs and priorities of the individual's family and other social environments, the evidence base, and the individual's response to intervention. This approach is especially relevant to AAC intervention for young children with complex communication needs given their unique constellations of strengths and challenges, and the qualitative and quantitative changes that they experience over time as they develop, as well as the diversity of their families, schools, and communities. This article provides detailed documentation of personalized AAC intervention over a 6-month period for a 3-year-old girl with developmental delay and complex communication needs. The article describes (1) personalization of multimodal AAC supports to provide this child with the tools to communicate; (2) personalized intervention to build semantic and morphosyntactic skills; and (3) personalized instruction in literacy skills (i.e., letter sound correspondences, sound blending, decoding, sight word recognition, reading simple stories, reading comprehension, and encoding skills). Specific goals, instructional materials, and procedures are described; data on speech, language, and literacy outcomes are presented.