This document discusses challenges and approaches for site and patient recruitment in rare disease clinical studies. Key challenges include the rarity of diseases, difficulty finding patients and physicians, complex logistics, and vulnerable patient populations. Effective approaches involve casting a wide net globally, leveraging registries and advocacy groups, using medical informatics to identify sites, and hiring specialists to assist with outreach and education. Lessons learned emphasize starting recruitment efforts early, challenging site estimates, and ensuring multiple potential enrollment sites are identified for each patient.