This monograph studies ancient tefillin (also known as phylacteries) and mezuzot found in the Caves of Qumran. Most of these miniature texts were published by the end of 1970s and thus have long been available to scholars. And yet in several respects, these tiny fragments remain an unfinished business. A close scrutiny of their editions reveals a presence of texts that have not been fully accounted for. These fall into three categories. First, there are multiple tefillin and mezuzot that contain legible fragments which their editors were unable to identify. Second, several tefillin and mezuzot feature imprints of letters that have not been deciphered. Third, there are texts which were provisionally classified as tefillin and mezuzot yet left unread. This monograph offers a detailed study of these unidentified and undeciphered texts. It thus sheds new light on the contents of ancient tefillin and mezuzot and on the scribal practices involved in their preparation.