We examined how different drivers of infectious disease could interact to threaten control efforts in Europe. We considered projected trends through 2020 for 3 broad groups of drivers: globalization and environmental change, social and demographic change, and health system capacity. Eight plausible infectious disease threats with the potential to be significantly more problematic than they are today were identified through an expert consultation: extensively drug-resistant bacteria, vector-borne diseases, sexually transmitted infections, food-borne infections, a resurgence of vaccine-preventable diseases, health care-associated infections, multidrug-resistant tuberculosis, and pandemic influenza. Preemptive measures to be taken by the public health community to counteract these threats were identified.