Complex patterns in plant vegetation growth, or productivity, in the Artic tundra and boreal forests have been observed. These patterns have shown varying trends over time and space, yet factors driving these patterns and changes remain poorly understood. Some areas show increases in productivity, known as “greening” or decreases, known as “browning.” Changes in vegetation productivity can have strong implications for how ecosystems function and may influence climate and other global processes. This workshop brings together experts to discuss the causes of observed patterns, the tools to measure them, and how to reduce existing knowledge gaps to improve understanding.