This book focuses on the latest developments in psychology research. Chapter One discusses current advances on cognitive rehabilitation in fibromyalgia and chronic fatigue syndrome. Chapter Two examines the nature of clinical reasoning in terms of critical thinking. Chapter Three presents some theoretical directions in social psychology that have served as a basis for research into disability. Chapter Four reviews a challenging approach concerning the cognitive strategies used in problem solving situations by boys with and without intellectual disabilities using Markov chains. Chapter Five reviews the advances that have been made in research on callous-unemotional traits. Chapter Six analyzes gender risks in Developmental Coordination Disorder. Chapter Seven provides a complex trait-based approach to the understanding of narcissism. Chapter Eight contributes to a better understanding of the limits of an important group decision model. Chapter Nine highlights and discusses unique challenges to the implementation of advance directives, as well as other issues that may arise during the care of patients with terminal dementia. Chapter Ten provides the reader with a selective overview of the intervention options available in the literature within the last sixteen years for assessing and recovering post-coma persons in a vegetative state. Chapter Eleven concludes with a structural analyses of members’ relationships in a Selective Mutism family.