The Diocese of Rockville Centre is a Roman Catholic diocese located on Long Island, New York. Established in 1957, it serves a diverse population of over 1.5 million Catholics across Nassau and Suffolk counties. The diocese is part of the larger United States Conference of Catholic Bishops and focuses on spiritual growth, education, and community service. The diocese is led by a bishop, currently Bishop John Barres, who oversees various parishes, schools, and ministries. It emphasizes the importance of faith formation, social justice, and outreach programs to support the local community. The diocese also engages in ecumenical efforts to promote unity among different Christian denominations.