What is amazing among all the growing aspects in a child is language development. None can ignore the fact that, a mother, father other family members or even relatives wait longingly and impatiently for the first moments a child starts producing sounds, words, and even reacting and responding to certain actions and behaviours consciously. Therefore, when it happens that a child (A) is unlike child (B) in terms of linguistic abilities, it is a sign that such a child is abnormal and the sad story will start. That is, individuals who have poor communication skills are clinically diagnosed with pragmatic language impairment due to different types of developmental dysphasia. For that matter, this book presents these two issues where the two topics are synthetically introduced, and assessment tools in the Arabic Language of individuals with PLI and DD, namely the Test of Pragmatic Language TOPL-2, and two subtests from the Clinical Evaluation of Language Fundamentals CELF-4 are also presented in three studies: two quasi-experimental and a multiple case-study. Hence, the book is directed to speech and language pathologists along with researchers in clinical, psycho-neuro-bio-linguistics.