We have better information on an unreached people group living in the Himalayas than we do on that same group living in your North American city. This is one of the reasons I wrote Strangers Next Door: Immigration, Migration, and Mission. More and better research is needed.
Research done by Global Research, Joshua Project, and the World Christian Database has provided the Church with excellent information on people groups across the countries of the world. The only two exceptions are the United States and Canada.
The governments of these two countries know nationalities represented within their borders, but not people groups. For example, the U. S. government can tell us how many people from Afghanistan live in the United States. However, Afghanistan is comprised of 39 people groups. We have no public information 
on which of these 39 groups are represented in this country. Such information is extremely important for strategy development. Just as all U. S. citizens are not the same, much variation can be found among the 39 people groups of Afghanistan.
PeopleGroups.info is making an attempt to identify who is living in the 100 largest U. S. metro areas and 5 largest Canadian metro areas. Part of their approach is training people to conduct their own research in their communities. If people in their locales do not make an effort to study their communities, then it is unlikely that we will ever know who is living among us.
There are four more Discover and Engagement workshops scheduled for 2015. According to their site, they are open to scheduling workshops as well.
We hosted one of these events last year for The Church at Brook Hills. I strongly urge you to be a part of one of these training sessions this year, or bring one to your area. It has changed our local church planting strategy and how we think about reaching the nations.
On the Saturday afternoon of the workshop, 40 of our members (with no background in field research) scattered across Birmingham (pop. 1.5 million) for only four hours. The result was that we encountered 34 different nationalities–with most of these representing unreached peoples (and most of these unreached were unengaged in Birmingham). This photo shows our whiteboard results.
Since this time, we have organized eight church planting teams for our city to focus on unreached people groups. They are beginning their Kingdom efforts this year.
The Spirit can lead us with information we do not have (see much of Acts). However, God has often worked in powerful ways to move His people when they receive a report from the field (Nehemiah 1-2).
There are many conferences and training events you and your people can attend in 2015. If you can only select one, this is the one you should select. It will open eyes in ways that words alone cannot.
Great Post. Thanks for highlighting this issue. One further thought I would contribute is a concern that I have. When I encounter churches that want to engage these immigrant communities they almost always adopt a “come and see” model. This is in stark contrast to the incarnational model of ministry adopted by most cross-cultural workers. Nothing beats going into other people’s homes, eating their food, learning their language and genuinely loving them for who they are. Too often, we take the programmatic approach of offering ESL courses and the like in an attempt to get them to come to us. Neither approach needs to be used exclusively but most churches easily adopt “come and see” without realizing the enormous cultural bridge that people must cross to do this.
Thanks Ted. Great comment. Yes, we need to meet people where they are in our communities. I was told yesterday of two members who are starting ESL at a nail salon where most of the women are from Asia. Rather than attempting to get the women to come to us, they have permission to do ESL in the salon.
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