NSCLC is an area of oncology in which clinicians are beginning to use specific tumor-associated molecular aberrations to assign and/or prioritize targeted therapies for patients. At this early stage, multiple hurdles remain before molecular profiling becomes a routine part of thoracic oncology practice. In particular, to develop specific targeted therapies for patients whose tumors harbor rare mutations, it will be important to identify appropriate candidates, design the appropriate trials, and execute the trials with adequate numbers to achieve the necessary endpoints. Implementation will facilitate realization of the promise of molecularly tailored therapy, which could lead to more effective treatments with fewer side effects.