I have, across the board, been rejected from all ten REUs that I applied to. A lot of them (CERN, Perimeter, SULI) make sense because of how prestigious they are, but I also failed to get into lesser know programs such as DAAD-RISE, Baylor, Columbia, Cornell, Indiana, Will&Mary, and Duke. I'd like to know what it is that killed me so I can try to improve it if I choose to re-apply next summer, or go to grad school. I am a Junior in an accelerated masters program, doing a BS in physics/math and an MS in physics. I have taken 18+ credits every semester since sophomore year, and my cumulative gpa is 3.5 (is this competitive?) and a physics gpa of 3.7. During the summer of my sophomore year, I worked in my university's nuclear lab doing random experiments on decaying isotopes as per the will of my supervisor; it was mainly calibration, checking attenuations of various materials, finding activities, and so on. I have done theoretical work in quantum mechanics with a different professor, where our goal was to provide an extension of Bohm Theory into Special Relativity (this has been put on the back-burner because the professor had to take the semester off due to illness). I have also begun my senior project with yet a third professor, in the field of chaos theory. I might not be the most amazing candidate in the world, but I think I have very reasonable grades and some research experience, so I don't quite understand why I couldn't have gotten into at least one program. What am I missing, and what can I do to improve my prospects?