Written by an autistic psychologist specializing in neurodivergent adult assessments, this pioneering book bridges the chasm between clinical practice and autistic experience via the author's unique and candid "insider-outsider" perspective. Divided into three sections covering foundational knowledge, building connections, and clinical applications, this book integrates personal insights with extensive clinical experience, research, and perspectives from the autistic community, sharing both the author's own late discovery of autism and the parallel challenges high-masking autistic adults often face in receiving appropriate care. Readers will learn to look beyond a performance of "normalcy" to understand the internal worlds of their clients, addressing the sensory, social, and emotional experiences that are often missed and misunderstood. Chapters provide clinicians with foundational knowledge and practical strategies to address autistic burnout, complex trauma, social anxiety, co-occurring conditions, and differential diagnosis. Ideal for healthcare professionals working with autistic adults, this book advocates for empathetic, informed, and compassionate healthcare practices and highlights the need for a nuanced appreciation of autistic adults' complex experiences.