Extensive public-private partnerships, including the National Institutes of Health (NIH) and the rare diseases community, which is seeing a renewed industry interest in smaller niche markets, have resulted in an increase of interventions for rare diseases. Significant collaborative efforts are required among the pharmaceutical industry, foundations, patient-advocacy groups, academic and government investigators and funding programs, regulatory scientists, and reimbursement agencies to meet the unmet diagnostic and treatment needs for approximately 25 million people in the United States with 7,000 rare diseases. The expanding role and outreach activities of patient-advocacy groups have increased public awareness. In the United States, a rare disease is defined as a disorder or condition with a prevalence of < 200,000 people. In 2011, the NIH provided > $3.5 billion for rare diseases research, including $750 million for orphan product development activities, nearly 11.4% of the NIH research budget. Several research institutes and centers of the NIH, including the National Center for Advancing Translational Sciences, have initiated varied translational research efforts to address the absence of preclinical and clinical data required for regulatory review purposes. Clinicians can expect to see significant increases in requests from patients and their families to participate in patient registries and natural history or observational studies to gather specific information from a larger pool of patients on the progression of the disease or response to treatments. An expanding emphasis on rare diseases provides hope for the millions of patients with rare diseases.