The award provides up to five years of support consisting of two phases. The initial award (K99) provides one to two years of mentored, postdoctoral support. The second phase (R00) provides up to three years of independent research support and is activated when the awardee accepts a full time tenure track (or equivalent) faculty position. Applicants must be in postdoctoral positions and may be at nonprofit, for-profit, or governmental agencies, including intramural NIH laboratories. Both U.S. citizens and non-U.S. citizens are eligible.