Dear Justin, We've heard about the 10/40 Window for 30+ years. Is it still as urgent that we go to the 10/40 Window? Joshua Project has an excellent description of what, precisely, the "10/40 Window" is. It began in the heyday of the AD 2000 & Beyond Movement as a mobilization tool for referring to the least-reached peoples. At the time, I worked with the World Christian Encyclopedia, which used the terms Worlds A, B, C to refer to the unreached (World A, the unevangelized; World B, the evangelized non-Christian world; World C, the Christian world). The 10/40 Window was stickier, I guess, because it was easily understandable: the area between 10 degrees and 40 degrees north of the equator. This area has also been called the "Resistant Belt." I think World A didn't catch on because it wasn't immediately memorable (what does it mean?); the "Resistant Belt" probably didn't catch on because it carried an implied judgement which might or might not be true. (In fact, I'd argue that it's mostly not true--peoples within the 10/40 Window can be moreresponsive than the West.) Is it still urgent that we go to the 10/40 Window? To me, the answer is a clear and obvious "yes"--because as of yet we still haven't seen the a significant headway in the remaining task there. This week, I'm working on an Outlook for Bihar, a province of India (which is firmly within the 10/40 Window). It has over 100 million people in some 39 districts--and most of those districts are 0.0% Christian. No believers. In most of the 10/40 Window, it's not because they reject Christianity--it's because they haven't heard of it. 86% of Muslims, Hindus and Buddhists do not personally know a believer (and this global average is far higher in the 10/40 Window than in the West). Unfortunately, in my experience, a lot of people have "heard the hype" of the 10/40 Window--and they assume because there's been marketing hype, people have gone. But that's just not the case. (Yes, work has been done in the Window, and quite a lot of it. But not enough.) So it's just as urgent to go to the Window today as it was 30 years ago... because in the past 30 years, we honestly just haven't responded to the challenge as we should have, and today there's even more people living in darkness than there were then. Have a missions question? Email email@example.com, and I'll find the answer and post it here.