This book is an annotated critical edition of an unpublished collection of hymnographical texts, preserved in the 11th-12th-century Greek manuscript 11 of the library of Leimonos monastery, Lesbos, Greece. This important codex is a Menaion for June comprising thirty akolouthiai on saints; twenty of them are hitherto unpublished. The edition of the texts is accompanied by an introduction, a commentary, appendices of unpublished hymns preserved in manuscripts other than Lesbiacus Leimonos 11, a full bibliography, indexes and plates with facsimiles of selected folios of manuscripts.