This guide to Williams syndrome (WS), a congenital disorder characterized by developmental/cognitive limitations but relatively high verbal and social skills, explains the strengths, difficulties and variations found among individuals with the condition and offers guidelines for intervention in the unusual properties of the WS behavioral profile. Following an introductory chapter, chapter 2 describes strengths and weaknesses of people with WS in various language areas including language acquisition, semantics, syntax, pragmatics, discourse, and storytelling. Chapter 3 addresses ways in which the language problems may be addressed. Chapter 4 focuses on the visuospatial deficits and strengths, motor deficiencies, and visuomotor integration problems of people with WS as well as their auditory hypersensitivity, tactile hypersensitivity, and skills in these areas. Chapter 5 consider four areas of specialized skills associated with WS: sociability including empathy, curiosity, memory, and musicality. Chapter 6, on maladaptive behaviors, describes six kinds of behavior problems often manifested by these individuals: anxieties and fears, distractibility and attention problems, impulsivity, poor adaptability, low frustration tolerance, and atypical activity. The final chapter summarizes the material on the behavioral characteristics of people with WS and considers how it may be synthesized into an integrated, overall profile of WS. An appendix provides an annotated guide to resources. (Contains approximately 425 references.) (DB)