Weak systems for health hit the poorest and most vulnerable the hardest. These are the people who often are least able to access health care because they are unable to pay or because they live too far from any health care facility. The Ebola crisis in West Africa was a wake-up call and revealed the unique problems that occur in challenging operating environments. Health and access to health care needs to be understood as part of a development continuum. And investments in systems for health need to be targeted based on where a country stands on that development continuum. Investments in programs for AIDS, TB and malaria build stronger health systems because they free up resources to treat other conditions. For example, people suffering from AIDS-related illnesses once occupied 90 percent of all hospital beds in sub-Saharan Africa. That percentage has plummeted. Inpatient admissions for malaria have also declined significantly, making hospital space and health care professionals available to treat other illnesses.