Wood decomposition is usually brought about by a community of fungi which interact with each other, and with other organisms. The structure and activity of these communities change with time, and in response to the presence of other organisms and environmental conditions. Understanding fungal community structure and dynamics is essential for modeling and predicting ecosystem function in a globally changing environment. While solid progress has been made on describing wood decay communities in the 20th century, with modern technologies we are now able to achieve a deeper understanding, and the time is now ripe to review recent, exciting progress.