The Mormon church just welcomed its 10 millionth member. Mormons have joined the mainstream -- the once insular church of the Salt Lake Basin now preaches in 161 countries. In the hour of To the Best of Our Knowledge, exploring the success of the Church of Jesus Christ of Latter-day Saints. Also, the Mormon pioneers' trek to the promised land; Terry Tempest Williams on nature and the Mormon tradition; and a feminist slant on polygamy.

SEGMENT 1:

William Slaughter is an archivist for the Historical Department of the Church of Jesus Christ of Latter-day Saints, and co- author (with Michael Landon) of "Trail of Hope: The Story of the Mormon Trail." He tells Judith Strasser about the vanguard group of Mormon pioneers and their thirteen hundred mile trek to the Salt Lake Basin. Also, naturalist Terry Tempest Williams credits her Mormon heritage with instilling in her a love of nature. She tells Steve Paulson how respect for the environment grows out of the Mormon tradition. Williams is the author of "Refuge" and "Desert Quartet."

SEGMENT 2:

Jan Shippes is a professor emeritus of history and religion at Indiana University, Purdue University, Indianapolis. She tells Jim Fleming about the Mormon Church tenets that give rise to their strong moral and family values. Also, outsiders still associate polygamy with Mormonism even though the Church outlawed plural marriage over a hundred years ago. Outside the Church, however, polygamous communities still exist. One of Alex Joseph's eight wives, Elizabeth Joseph is a lawyer, teacher, radio executive, and feminist. She tells Steve Paulson that her polygamous marriage is perfectly consistent with her feminist principles.

SEGMENT 3:

Alex Shoumatoff is the author of "Legends of the American Desert: Sojourns in the Greater Southwest." He tells Steve Paulson that the Mormons are only one of many cultures found in the Southwest, but that the aridity of the region has shaped all of them.

Distribution dates:

• week of 12/07/97 - hour 1