Justified setting is one of the most common configurations of a block of text. It is found across different cultures, writing systems, and languages. Yet whilst the concept of equalising the width of lines in a column to achieve a rectangular block is shared, the techniques that are employed towards this end are diverse. This paper discusses the justification of Arabic text. It lays out the methods that evolved in manuscript practice and reflects on their interpretation in typography. A short history contextualises how Arabic justification changed under the influence of technology and prepares the ground for a review of the provisions found in current typographic environ-ments. The paper then presents the state-of-the-art of digital text layout for Arabic and queries its suitability. Contemporary tools are then juxtaposed with a review of the justification tech-niques that are found in exemplary models of manual typography, presenting evidence that un-derlines shortcomings of current methods and software implementations. The argument con-cludes with recommendations of best practice aimed at toolmakers and designers of Arabic doc-uments
