Regular monitoring of vaccination practices and attitudes is essential for setting vaccination policy priorities, evaluating them, and implementing appropriate strategies to improve the outcomes of these policies. The Health Barometers—cross-sectional surveys conducted regularly by INPES—have made this possible for nearly twenty years. The latest round, conducted in late 2009 and early 2010—during the H1N1 influenza pandemic and the decline in participation in the vaccination campaign—allows for the observation of these indicators within this very specific context. It also provides an overview of the main trends observed during the first decade of the 2000s.