Twenty-eight parishes will be grouped into 12 clusters, or collaboratives, in the first phase of a reorganization plan by the Roman Catholic Archdiocese of Boston:

■ St. Luke and St. Joseph, Belmont.

■ St. Mary, St. Margaret, St. John, Beverly.

■ St. Mary, St. Theresa, St. Andrew, Billerica.

■ St. Mary of the Assumption, Brookline (a one-parish collaborative)

■ St. Mary of the Angels, Roxbury, and St. Thomas and Our Lady of Lourdes, Jamaica Plain.

■ St. Mary and Sacred Heart, Lynn.

■ Our Lady of the Assumption and St. Maria Goretti, Lynnfield.

■ St. Lucy and St. Monica, Methuen.

■ Sacred Heart, Middleborough, and Sts. Martha and Mary, Lakeville.

■ Sacred Heart and Our Lady Help of Christians, Newton.

■ St. James, St. John, Immaculate Conception, St. Anne, Salem.

■ St. Jerome and Immaculate Conception, Weymouth.