Summary. Rare disease research is increasingly challenging. For those with haemophilia, this is an exciting time, with the promise of new therapies at the bench and in early phase clinical trials. Yet, it is also a time for critical assessment and planning to assure the success of the clinical research effort. As successes at the bench have enabled transition of novel peptides, longer-acting factor products and gene therapy to clinical trials, clinicians face the challenges of limited number of patients, competing priorities and strained resources. To solve these problems and assure the success of the clinical research effort, it is essential that the research process be enabling and the dialogue be global, involving academia with industry, and physicians with patients. This is a critical juncture in the process, especially with new national initiatives in clinical research at hand. Needs must be assessed and priorities must be set to assure that despite the challenges, exciting new therapies will ultimately translate into safe, effective therapies for patients. Finally, these challenges are by no means restricted only to rare disease research. With the evolution of genetic medicine, it is likely that the general medical disease research of the future will include small clinical trials of new agents for small subsets of patients with certain disease mutations. Thus, the milestones we achieve in this ongoing process will hopefully not only enable clinical trials research in a rare disease, but also in many medical genetic disease of the future.