Contrary to popular perceptions of homelessness as a static, enduring condition, we emphasize its dynamic nature. The updated macro-micro framework that we develop capitalizes on the increasing availability of over-time data, which makes it easier to examine changes in homelessness and the factors responsible for them. Our framework integrates structural forces—such as income inequality, an affordable housing shortage, social exclusion, and inadequate safety net programs—with the personal circumstances and challenges that shape individuals’ homeless trajectories. The macro-micro perspective also helps us to evaluate the effectiveness of policies, and it highlights variation across contexts in how the dynamics of homelessness operate. In a separate section, we introduce the sixteen core articles of this volume against the macro-micro backdrop. Finally, we discuss two emergent macro “shocks” (the COVID-19 pandemic and climate-related hazards) that are largely absent from the volume but carry important implications for understanding and addressing homelessness in the future.