In preparation of the Synoptic Gospels in the series Editio Critica Maior all variants found in 159 Greek manuscripts in 41 parallel pericopes are documented in a critical apparatus with a synoptic layout. Thus this new special edition offers a broad basis for research into the influence of textual parallels on the formation of variants. Moreover, the full variant apparatus enables studies on patterns and tendencies of variation in the manuscripts included. For most of them such research has hitherto been dependent on the relatively small sample of evidence provided by test passage collations.