In The Hunchback of Notre Dame, Victor Hugo waxes eloquent on the decline of cathedrals and of their impact on Christianity. Claude Frollo, the archdeacon of the cathedral, points to a book, then to Notre Dame, and predicts, “This will replace that.” As new printing technologies made the written word more accessible, books would supplant churches as the primary means by which everyday people encountered God. His prediction came true. Cathedrals were built not only to house teaching and worship, but to proclaim the gospel and convey doctrine, theology and Scripture. Now we use other technological means to do the same. In Hugo’s day, the primary means was the book. Today it’s the blog, the podcast, Twitter and Instagram. With the advent of new ways to communicate the gospel, we can afford to expect much less of our buildings. It is unlikely that any generation—let alone Millennials, who are so at home in the digital space—will seek to recreate the physical spaces of the past. But the question is worth asking:  What are we losing along the way? As we develop religious spaces fit for the 21st century, how can we also maintain the timeless principles of sacred space that have been developed through centuries of architecture and design? The old churches were built to connect people to God. The altar, the stained glass windows, the soaring ceiling that pointed to the heavens—every element was designed to create a link between human and divine. Modern churches typically are not designed with this goal in mind. As my colleague Clint Jenkin wrote in another Aspen blog post, “In fact, many modern churches are explicitly constructed not to look and feel too much like a religious place. A modern church is designed to host activities, and these activities point the people to God. But strip away those activities and you might as well be at a community college or a performing arts center or, heaven help us, an airport terminal.” Most of our modern churches have excellent areas set aside for corporate worship, group learning, and community building. But they leave something to be desired when it comes to personal reflection and prayer. How do these changes impact Millennials? I’ll be taking a deep dive into this critical question at this year’s Alignment Conference. You’ll also receive a copy of the new Barna study on Millennials and church architecture when you attend the conference. Millennials may or may not be the next “greatest generation,” but they are certainly the next largest. With about 78 million of them in the U.S., they are an important demographic for any organization to understand, and churches are no exception.