Across the globe, researchers are building massive databases of health information on patients and people with neurodegenerative diseases, including Alzheimer’s and amyotrophic lateral sclerosis. What can scientists learn from these initiatives and from the piles of health data now accumulating in electronic medical records? To find out, Amber Dance attended the Meaningful Use of Complex Medical Data Conference in Los Angeles. Read the story to find out how data are being used to make medical decisions and predict illness and recovery, and learn about the challenges in turning health records into useful guidelines.