Euchologion

thumb|A private-use Euchologion produced by Eastern Catholics

The Euchologion (Greek: ; Church Slavonic: , Trébnikъ; ) is one of the chief liturgical books of the Eastern Orthodox and Byzantine Catholic churches, containing the portions of the services which are said by the bishop, priest, or deacon. The Euchologion roughly corresponds to a combination of the missal, ritual, and pontifical as they are used in Latin liturgical rites. There are several different volumes of the book in use.