STEM fields include biology, chemistry, and physics; all forms of engineering; computer science; and math. Labs in these disciplines are extremely expensive and often require substantial equipment and research support. Fellowship funding provides faculty with the flexibility to pursue new research directions, deepen current areas of study, and build a stronger portfolio of findings. The Fellowship also paves the way for other funders to confidently support research with large dollar grants and awards. Hellman Fellows in STEM fields are advancing understanding and tools to address critical issues including carbon emissions, seismology, solar energy, and brain chemistry.