"A Parent's Guide to Assessment" is the fifth volume in the "Life Journey through Autism" series published by the Organization for Autism Research (OAR). It is intended to remove the mystery surrounding assessment, provide parents with a practical understanding of the assessment process, equip them as a parent with the knowledge and confidence to become a key participant in the process, and help them learn to use assessment outcomes to improve services and interventions for their child. The information contained in this guide, however, has utility for everyone engaged in supporting individuals with an autism spectrum disorder (ASD) in their efforts to develop higher skills and attain greater degrees of personal competency. The topics covered in this guide include: (1) Definition, purposes, and uses of assessment; (2) Strengths and weaknesses of the assessment process; (3) Types of assessments and what each tool measures; (4) Finding the right assessment professional; and (5) Translating the language of assessment into their child's life plan. This guide begins with a general overview of what assessment is, how the process is supposed to work, and why it is important. It then describes the types of assessments that parents and their child may encounter, the purposes of each, and the different skills and abilities that various instruments assess, including cognitive abilities, speech and language skills, and social functioning. It progresses to describe the assessment process, the people who conduct the assessments, and what happens during an actual assessment. Finally, the guide will suggest ways in which parents can use assessment results to improve the services their child receives. Six appendices are included: (1) Overview of Assessment Terms; (2) Questions to Ask Before and After an Assessment; (3) How to Prepare for an Assessment; (4) Frequently Used Standardized Assessments; (5) Evaluation Review Chart; and (6) Resources for Parents. Individual chapters contain references. (Contains 1 figure, 9 resources, and 8 online resources.) [This publication is a product of the collaborative effort between the Organization for Autism Research (OAR), the Southwest Autism Research & Resource Center (SARCC), and Danya International, Inc. (Danya), with support from The Doug Flutie, Jr. Foundation for Autism. Suzanne Letso authored the section of this guide titled "Evaluation for Educational Placement."]