Two groups are officially counted as members of The Church of Jesus Christ of Latter-day Saints. The first includes living individuals above the age of eight who have been baptized and confirmed by those with proper priesthood authority. Individuals baptized but not confirmed remain on membership rolls for one year, after which time local congregations are instructed to remove their names if the ordinance of confirmation has not been completed.
Once baptized and confirmed, individuals remain on membership rolls for life regardless of whether they continue to attend church or even whether they identify themselves as Latter-day Saints. A member is removed from church membership rolls if he dies, if he is excommunicated for apostasy, or if he completes a voluntary name removal process. Inactivity in the church is not considered grounds for excommunication.
The second group of members consists of children below the age of eight who have been blessed in the church and the children of adult members. Bennion and Young noted, "Although Mormons reject infant baptism, they count as members any 'children of record' blessed and named soon after birth. Thus unbaptized children of members (until age eight) make up an important share of the LDS population (about 15 percent among Americans)." These members, called "children of record," remain on membership rolls. At age eight, children are baptized and confirmed and become lifetime members. If not baptized by age nine, the child is removed from membership rolls.
Although some critics have questioned the authenticity of LDS membership numbers, the Church's meticulous record keeping suggests that membership numbers are reliable. It is the question of what these numbers represent that should occupy our attention. The Church makes no claim that official membership numbers reflect active or participating members. A news item in the Church's Ensign magazine observed:
"Church membership growth numbers are often interpreted inaccurately, which can lead to misconceptions in the media, Brother Buckner said. Therefore, it is important to clearly understand what these numbers signify. They represent the number of Church members, but they do not represent activity rates. The Church does not remove an individual's name from its membership rolls based on inactivity."
Misinterpretations of membership data are not confined to the secular media. An official church press release ahead of the April 2005 LDS General Conference was entitled: "Over 12 Million Worldwide United in a Single Purpose." A review of conference talks over the last few years found numerous citations referring to the total LDS membership of twelve or thirteen million members as individuals who believe in the Book of Mormon as the word of God and who accept Joseph Smith as a prophet. I will not cite names or citations out of respect for the speakers, but readers can readily verify the widespread practice of construing total membership numbers to represent believing, if not participating, members. Claims attempting to link official membership numbers with actual member participation or belief overreach the data. Greater care is needed both on the part of the secular media and church officials in accurately representing membership data.
Although the LDS faith is commonly regarded as a high-requirement faith, its definition of membership is closer to that of the Catholic Church and low-demand groups that report individuals as members indefinitely regardless of activity or participation. Other high-demand faiths define membership more stringently: the Seventh-Day Adventist Church reports as members only those who attend Sabbath meetings, and the Jehovah's Witnesses report as members only baptized individuals over the age of fifteen who are regularly involved in proselytism. As a result, direct comparisons of membership numbers may be unhelpful or misleading when individuals are not aware of the different membership definitions.
For example, statistics of thirteen million LDS members and six million Jehovah's Witness members would lead the average reader to conclude that the LDS Church has more committed members than the Jehovah's Witness faith. Yet statistics which will be presented in more detail later in the article sections suggest that less than one-third of Latter-day Saints, or about four million, attend church on an average week. The Jehovah's Witnesses statistical reports cite attendance of some fourteen million at their semiannual conferences, or more than double their official membership, with unbaptized affiliates and children of members and constituting the difference. By paper membership numbers, the LDS Church thus appears to be twice as large as the Jehovah's Witness organization, yet in fact nearly three times as many people actually attend Jehovah's Witness meetings as attend LDS congregations. This does not mean that either LDS or Jehovah's Witness data is erroneous or that statistics reflect any attempt to mislead. Rather, church membership is defined so differently that no valid comparison can be made without carefully considering these differences.
 Bennion, Lowell C. and Lawrence Young, "The Uncertain Dynamics of LDS Expansion, 1950-2020," Dialogue, Spring 1996: 8-32.
 "Membership, Retention on the Rise," Ensign, June 2007, 75-76.
 "Over 12 Million Worldwide United in a Single Purpose," LDS.org press release, April 1, 2005, www.lds.org.