This paper explores the ups and downs of innovation and productivity growth in the US economy and potential connections to the ups and downs of business dynamism and entrepreneurship over the last few decades. The 1990s and early 2000s exhibited rapid innovation and productivity growth. Productivity growth has slowed since the mid-2000s in a somewhat surprising manner – especially to those who monitor advances in innovation with apparent ongoing advances in cloud computing, robotics and automation. In the high productivity growth period of the 1990s, the US exhibited a highly entrepreneurial and dynamic economy. Indeed, policymakers in the late 1990s and early 2000s highlighted these factors as being critical for the surge in productivity during this period. In the productivity slowdown period, indicators of entrepreneurship and dynamism have slowed down and there has been an increase in the concentration of economic activity in large, mature firms. Interestingly, there are initial signs of a reversal in these dynamics as the US has emerged from the pandemic.