This is an overview of big bang nucleosynthesis (BBN), with an emphasis on the "lithium problem" -- which is mostly discussed in slides I had to skip because I was too chatty! I did not much emphasize the neutrino physics aspects of BBN, which George Fuller will discuss next week. As long as I am including material that I didn't discuss live, I also added a discussion of cosmic ray nucleosynthesis, which is responsible for the production of the nucleosynthesis "orphans" 6Li, Be, and B. Thanks to all the students for your great questions and enthusiasm. This was great fun, and inspiring to see that there is so much promise for the future! Lecture sides: {{:bdfields_talent6.pdf|Primordial Nucleosynthesis, the Lithium Problem, and Cosmic-Ray Nucleosynthesis}} ~~DISCUSSION|Big Bang Nucleosynthesis~~