The Novena to Saint Joseph is a Roman Catholic Novena

Novena

In the Catholic Church, a novena is a devotion consisting of a prayer repeated on nine successive days, asking to obtain special graces. The prayers may come from prayer books, or consist of the recitation of the Rosary , or of short prayers through the day...

 prayed to Saint Joseph

Saint Joseph

Saint Joseph is a figure in the Gospels, the husband of the Virgin Mary and the earthly father of Jesus Christ ....

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Like all other Novenas it is prayed on nine consecutive days with a specific intention. There are multiple forms of this Novena and in 1876 Pope Pius IX granted indulgence

Indulgence

In Catholic theology, an indulgence is the full or partial remission of temporal punishment due for sins which have already been forgiven. The indulgence is granted by the Catholic Church after the sinner has confessed and received absolution...

s, with the usual indulgence conditions, to all those who with a contrite heart pray the Novena at any time during the year based on a prayer approved by the Church.

The Memorare to Saint Joseph is one prayer that can be used for the Novena:

Remember, O most pure spouse of the Blessed Virgin Mary,

my sweet protector St. Joseph

that no one ever had recourse to thy protection

or implored thy aid without obtaining relief.

Confiding therefore in thy goodness,

I come before thee, and humbly supplicate thee.

Oh, despise not my petitions,

foster-father of the Redeemer,

but graciously receive them.

Amen.