There exist about 150,000 premodern Arabic documents on papyrus and paper, of which about 2,500 have been edited. Another 10,000 unpublished documents are described or mentioned in papyrological publications. It is the aim of the Arabic Papyrology Database (APD) to give access to published texts and descriptions. For the APD, an entirely new approach of organizing Arabic text was developed. The APD presents texts in five levels that account for the peculiarities of the Arabic script system and the scribal practices. The first level provides a faithful diplomatic edition of the text as found in the document. The following levels document four steps of editorial interventions. On the second level, lines of characters are broken into single words. On the third level, lacking diacritical dots are supplied. On the fourth level, Arabic vowel signs are added, providing a full phonological representation. On the fifth level, a scientific Latin transliteration is given. Each element of the fifth level is connected to a lexicon and a list of grammatical forms. All levels contain variant readings and editorial remarks. At present, the APD contains 1,806 full-text documents and is freely accessible (http://www.naher-osten.lmu.de/apd).