Schaller presents four numerical barrier when people assemble. Almost all groups stabilize at 1) less than 7, 2) 8 to 17, 3) 35 to 40, and 4) over 40. Each of these four group takes different leadership techniques and has different leadership demands. Quite frequently the size of the classroom, chairs, and table arrangement dictates the upper limits to a group in spite of what leadership does.

The Rule of Forty

Schalar calls "the Rule of Forty" one of the most neglected rules of church administration.

"In general, whenever human beings gather in a voluntary association that emphasizes relationships with one another, there is a natural tendency to limit the size to fewer than 40 persons. Illustrations are numerous. Throughout history, all military organizations have limited the basic unit to fewer than 40. Major league baseball teams limit a team's roster to 40 in the winter and 25 after the season begins. The Lion's Club that wins the regional attendance award usually has fewer than 40 members. One-fourth of all Protestant congregations in North America average fewer than 35 in Sunday worship. Very few adult Sunday school classes, regardless of their enrollment, average more than 40 in attendance."

C. Peter Wagner in Church Planting for a Greater Harvest (Ventura, CA: Regal, 1990) page 131 states:

"The group dynamic theory that underlies this is the rule of 40. Forty people is the ideal size for everyone to maintain face-to-face relationship with everyone else. In a church setting the group can expand to 80 and sustain most of the interpersonal qualities. However, when it goes past 80 toward 200, the relationships are so stressed out that they can not longer handle the thoughts of strangers entering the group and thereby increasing the stress. Without knowing they are doing it or without even wanting to, they relate to strangers like two identical poles of magnets."

Futher research places the plateau around 35 to 40 in a volunteer association that gathers only one or two days a week. More frequent meetings can increase the number upward toward 80.

Basic sizes

According to Schaller, groups have four basic sizes.

1. One is the small face-to-face group. Nearly every researcher on small group dynamics reports that when a group grows beyond seven members, the benefits of the small group begin to erode. Seven is the point of diminishing returns. That is one reason why most committees naturally consist of five to seven persons.

2. The next size can be described as the "overgrown" small group. If members are well acquainted with one another and see each other at least once or twice a week, this group, which may range between 8 and 17 members, can still enjoy many of the small-group dynamics. This is the common size for the basic unit in military organization, the most common size for a church choir, a circle of the women's organization, the typical youth group, and the church council, vestry, or session.

   For most of us, 17 people is the most we can "keep track of" in our head, recall names without hesitation, and relate to continually. Beyond 17, it is easy for someone to be absent without being noticed, and it is difficult for everyone to take an active role in the discussion.

3. The next size of these groups, a "middle-sized group," is where the Rule of Forty begins to apply. Thirty-five or forty is about as large as a group can become with the relationships of members as the basic organizing principle. As a group grows toward 40, most of the techniques and principles for strengthening cohesion in a small group lose their value. These include using a circle as the basic seating arrangement, asking the participants to take a minute or two each to introduce themselves to the entire group, encouraging everyone to share actively in the discussion, expecting each member to relate to all of the other members of the group, and assuming that each member will develop a strong loyalty to the group.

   The middle-sized group is the transitional size between the overgrown small group and the large group. It is rare for the middle-sized group to be able to include more than 40 active participants on a continuing basis.

   For example, with over a hundred on the youth group rolls, we have only 30 to 35 involved. So the church made the make youth ministries the top priority for our new associate minister.

   Also, the attendance at the monthly men's meetings was 35 to 45. Every now and then, for a special program, as many as 70 may turn out, but that's not many considering we have over 200 active members.

   Again, when the church moved into the new educational building, a huge room available for a new adult class, It was decided that since none of our other adult classes averaged more than 35 attenders, one big class with an excellent teacher would make an easy entry point for newcomers. Six weeks after it started, the class had grown to 50. We were delighted. The room accommodates at least 90, and it was expected the class to grow to at least 75. Now, after a year, the class averages only 35 or 40.

4. The large group consists of more than 40. The focal point tends to be the leader and/or the task, not the relationships of the members to one another. When the attendance passes 40, three basic changes usually occur:
   1. absenteeism or dropping out tends to increase,
   2. many of the methods effective with smaller groups become counterproductive, and
   3. it usually is appropriate to replace small-group techniques with large-group management tools.

   Implications

   If the Rule of Forty is a natural and predictable phenomenon, it can have several useful implications for church leaders.

   1. As a diagnostic tool, it helps explain each of the issues raised in the introductory paragraphs.

   2. In congregations where groups or classes have leveled off with 12 to 24 regular participants, leaders have three basic choices:
      1. they can be content with the status quo;
      2. they can expand the number of small and middle-sized groups, with the expectation that some will stabilize in the 8-to-17-member range while others will plateau in the middle-sized group category; and
      3. they may introduce large-group procedures to enable some of the middle-sized groups to grow into large groups.

   3. Another implication can be seen by looking at those groups that fluctuate in size between 35 and 45. A common example in larger churches is the chancel choir. Very few adult choirs include more than 50 voices, but many include 40 or 45 and appear to violate the Rule of Forty. Closer examination usually reveals the choir director is using some large-group techniques, such as
      1. requiring a commitment from each member to the common task, i.e. the special Easter anthem,
      2. a strong leadership role for the director, and
      3. a longer time-frame for planning.

      Without a shift to a greater reliance on large-group techniques, a choir probably will continue to fluctuate between 40 and 45 voices on Sunday morning.

   4. For larger congregations with more than a couple hundred Sunday morning worshipers, the Rule of Forty suggests it may be useful to have someone on the staff trained in the care and feeding of large groups.

   5. Awareness of this rule can be useful when a congregation is interviewing candidates for youth director or program director, when a smaller congregation finds itself in a cycle of rapid growth, when the church is contemplating a building program, or when the leaders are preparing a church-growth strategy. In each case, the time has come to consider the value of large groups in the church and the need for large-group techniques.