The massive growth and influence of cities in our time confront Christian mission with an enormous challenge. The first problem is one of sheer scale and economics. It is critical that we have Christians and churches wherever there are people, but the people of the world are now moving into the great cities of the world many times faster than the church is. Christian communication and ministry must always be translated into every new language and context, but the Christian church is not responding fast enough to keep up with the rapid population growth in cities.