It was Father Fermin Francisco de Lasuen, Serra's successor, who carried out the dream. Lasuen located the Mission at the Chumash Indian village of Tanayan. Spanish name for the place was El Pedregoso or "Rocky Mound".  Padre Antonio Paterna, a companion of Serra, put up the first buildings and made the first converts. By 1806 some 250 neat adobe Indian houses, plastered, whitewashed, and having doors and moveable windows, were placed back to back in rows to the left of the mission. The adobe neophyte village was larger than any other mission village in California at the time.

Father Paterna built the first church of palisade construction early in 1787. In 1789 Paterna completed the second church of adobe with a tile roof. Fathers Jose de Miguel and Estevan Tapis completed the third church of adobe and tile in 1794. The third church was destroyed by earthquake December 21, 1812. Construction of the present church of stone began in 1815. It was finished and dedicated in 1820 with only one tower. The second tower was added in 1831. It fell in 1832 and was rebuilt in 1833. The present friary residence or monastery wing was built gradually, first one story, then a second was added. It was not finished until 1870. On June 29, 1925, an earthquake damaged the mission church and friary considerably. Restoration work was completed in 1927 and the Mission towers were reinforced in 1953.

The original purpose of the mission was the christianization of the Chumash Indians. This was considered accomplished by the 1830's. The mission was secularized in 1834. Mission lands were sold in 1846. Unlike many California missions, priests at Santa Barbara conducted services in the church after 1846. California became part of the United states in 1848. In 1865 President Abraham Lincoln returned the mission to the Catholic Church. From 1868 until 1877 Franciscans conducted a high school and junior college for boys at the mission. In 1896 a seminary was established at Santa Barbara Mission. Until the summer of 1968, the School of Theology for the Franciscan Province of St. Barbara was located in mission buildings.

Franciscan Friars continue to live and work today at Old Mission Santa Barbara. Friars work in various apostolates in the western states. They serve the Indians of Arizona and New Mexico as well as foreign missions. The parish of St. Barbara today uses the mission church.