Researches Hebrew piyyut and poetry from the Late Antique Period until the Middle Ages, as well as prayer and the history of prayer rites.
She acquired her higher education at the Hebrew University in Jerusalem, predominantly under the supervision of Prof. Ezra Fleischer. She has written about 15 books, and over 100 articles – among these a critical edition of R. Pinḥas ha-Kohen; a collection of all known shivata-cycles for the yearly Sabbaths, in accordance with the Scriptural lectionary cycles; a number of works on Late Eastern piyyut (9th-12th centuries), among them critical editions of the works of El’azar be-rabbi Qilar (not to be identified with the Classical Qilliri), Yehuda be-rabbi Binyamin, Yehoshua bar Khalfa, Yosef ha-Levi he-Ḥaver ben Ḥalfon, and others. She has composed a voluminous three-volume work on secular Hebrew poetry in Spain, and in her book Wherefore Have We Fasted?: Megillat Ta’anit Batra and Similar Lists of Fasts she investigated the multifarious sources and complex recensions of an early list of fasts. In her research she has also dealt with the special treatment accorded to Scriptural stories in the liturgical poetry of different periods (outstanding in particular in this area is her book A Poem for Every Parasha: Torah Readings Refelected in the Piyyutim); the manner of the incorporation of midrashim into piyyut; the analysis of various linguistic phenomena in the works of the payyetanim; the tracing of early customs, primarily those connected to prayer and Scriptural reading; and with various additional topics connected to poetry and piyyut. She has been fortunate to discover in the fragments of the Cairo Genizah many important works, amongst them two previously unknown fragments of the book of Ben Sira, new poems by R. Yehuda ha-Levi and others. Currently, she is engaged with Dr. Michael Rand of the University of Cambridge in the preparation of a critical edition of the piyyutim of R. El’azar be-rabbi Qallir, as well as in the writing of an extensive book on the history of the qedustha – an early, central genre of piyyut.