NASHVILLE, Tenn. – I had an extended conversation with a pastor of a church this past week. The topic was not that different from those I’ve had with church leaders for nearly 25 years. The pastor’s words were similar to those I’ve heard repeated hundreds of times: “We have a pretty good front door with a healthy number of guests. And we’ve had a steady increase in our number of new members. Our problem is really not the front door; it’s the back door. If we could just keep a fourth of all those who become involved in our church for a few months or more, we would be triple our size.”

He then asked the questions I was anticipating: “So how do we close the back door? What do we do to keep people from leaving our church or just becoming inactive?”

In our research of thousands of churches, we have found four common characteristics of congregations that have effective assimilation by almost any metric. But these churches that have effectively closed the back door are few in number, suggesting that the solution is easier said than done. Look at the four keys to effective assimilation. They are obviously not mutually exclusive.

Key No. 1: Membership high expectations. More is expected of members in high assimilation churches. Church discipline is more likely to be exercised in these churches as well. These churches typically have required entry point or membership classes. Becoming a part of these congregations is more than completing a card or walking an aisle. Members are expected to be involved and stay involved.

Key No. 2: Small group involvement. A concerted effort is made to get members and attendees involved in small groups. The form of the group may be a Sunday School class, a home group or a small group meeting elsewhere. The key is to get people connected to others, typically in weekly groups. The majority of small groups study the Bible or biblically related material.

Key No. 3: Ministry/missions involvement. High assimilation churches encourage people to be involved in ministry. A few even require ministry involvement prior to accepting someone into membership. Members who are involved in missions and ministry feel connected to the church. The Millennial generation, those born between 1980 and 2000, will not likely stay with a church at all if they are not involved in the ministries and missions of the church.

Key No. 4: Relational connections. In any organization, people stay connected more to other people than the organization itself. We are relational creatures. Local congregations are no exceptions. People are more likely to stay connected to the church if they have developed meaningful friendships and relationships with others in the church.

If these four keys are the solution to assimilation problems, why do relatively few churches practice them? Simply stated, the solutions require hard work. Often getting people in the front door is easier than keeping them from leaving through the back door.

Also, some churches have established traditions of low expectations. Changing almost anything, particularly expectations of members, can be a challenge. Members who came into the church with low expectations often resist the change. Their desired comfort is greater than their concern for the overall health of the congregation.

Our most recent research indicates that the American population as a whole is not resistant to visiting a church. The potential for an open front door is good. The greater challenge may be closing the backdoor.

And that challenge can only be met if congregations are fundamentally willing to change their attitude of “we’ve never done it that way before.”