How might law firms harness the transformational potential of technological change to drive exponential business growth? We are at the start of a Fourth Industrial Revolution--a wave of transformation fueled by powerful technologies such as artificial intelligence (AI). This could drive a bigger wave of growth in the legal sector than any other change in history. Previous transformations gave us steam-based mechanization, electrification and mass production, and then electronics, information technology, and automation. This new era of smart machines is fueled by exponential improvement and convergence of multiple scientific and technological fields.