Did you know that during the last 20 years the largest human migration in history has taken place—and hardly anyone in the outside world knew about it? This migration took place in China, when hundreds of millions of people left their home villages in the countryside to seek employment and a better life in big cities. The city where our training is based—centrally located in a region that contains hundreds of unreached people groups—witnessed a huge influx of people from the surrounding countryside. These are people who have no knowledge of Jesus, and no viable church among them.