ACLing 2018 is the fourth edition of the Arabic Computational Linguistics series (ACLing). The conference aims to bring together leading academicians, scientists, researchers and practitioners from all over the world to exchange new ideas and the latest results in Arabic Computational Linguistics and NLP. This field has become increasingly important, as more and more Arabic information is now available through the Web, Social Media and Intranet services. The scope of the conference encompasses the theory and practice of all aspects of Arabic Computational Linguistics in text, audio, image, and video. Arabic is the most prominent member of the Semitic family (and its dialects) which includes many languages and dialects spoken by a large number of native speakers (around 300 million). Arabic has a rich and productive pattern-based morphology and syntactic constructions. However, the Arabic language as a whole is still understudied and many of its computational systems are underdeveloped. The British University in Dubai has been chosen to organize and host ACLing2018 conference because it has a missionfor establishing itself as a provider of world class scholarship, education and research.