Accurate diagnosis of Autism Spectrum Disorder (ASD) at an early age is increasingly sought so that the child and family can access early intervention and supports. However, not all children neatly fit into the diagnostic criteria for ASD, and additional assessment and supports are often required as providers continue to evaluate the possibility of a diagnosis. This article illustrates the complexity of diagnosis and discusses a logical progression of assessments and interventions for Joseph, a then 32-month-old boy, initially referred for an evaluation because of speech and language delays. The authors discuss the difficulty of an uncertain outcome following assessment and intervention. They reflect on their own experiences and lessons learned over the course of the treatment and evaluation process.