Nation-specific registries of ART treatments were established in the United States, Canada, and Mexico in 1985, 1999 and 1995 respectively. In the United States, reporting became mandatory in 1992, and 94% of nearly the 500 clinics report. In Canada, reporting is voluntary and all but one clinic is currently reporting. In Mexico, a small proportion (about 20%) of over 50 clinics report to their country’s registry. Initially these registries contained summaries of each clinic’s overall outcomes, but all have now become cycle-specific. While all registries have systems in place to ensure quality of data, prospective reporting and annual data validations are mandatory only in the United States. All registries have adjusted their online data collections systems to capture changes in clinical practice patterns. Clinic-specific ART reports are available online in all North American countries. Information from these registries has been valuable for research and to develop treatment guidelines; most significantly, guidelines regarding the number of embryos to transfer has led to a dramatic reduction in multiple pregnancy rates.