The chapter assesses the phylogenetic position of Armenian within the Indo-European language family. After examining the most important, independent developments constituting Armenian as a separate language branch, it discusses those phonological, morphological, and lexical innovations that are shared with, in particular, Greek, Phrygian and Albanian. It then argues that these innovations are sufficiently numerous and significant to posit that together with those languages, Armenian belongs to a higher-order subgroup, Balkan Indo-European.