A Paraklesis (Greek: Παράκλησις, Slavonic: молебенъ) or Supplicatory Canon in the Byzantine Rite, is a service of supplication for the welfare of the living. It is addressed to a specific Saint or to the Most Holy Theotokos whose intercessions are sought through the chanting of the supplicatory canon together with psalms, hymns, and litanies.

The most popular Paraklesis is that in which the supplicatory canon and other hymns are addressed to the Most Holy Theotokos (the Mother of God). There are two forms of this service: the Small Paraklesis (composed by Theosterictus the Monk in the 9th century), and the Great Paraklesis (composed by Emperor Theodore II Laskaris in the 13th century). During the majority of the year, only the Small Paraklesis to the Theotokos is chanted. However, during the Dormition Fast (August 1—14, inclusive), the Typikon prescribes that the Small and Great Paraklesis be chanted on alternate evenings, according to the following regulations:

• If August 1 falls on a Monday through Friday, the cycle begins with the Small Paraklesis. If August 1 falls on a Saturday or Sunday, the cycle begins with the Great Paraklesis.
• On the eves of Sundays (i.e., Saturday nights) and on the eve of the Transfiguration (the night of August 5) the Paraklesis is omitted.
• On Sunday nights, the Great Paraklesis is always used unless it is the eve of Transfiguration.