Operations and co-operations in Morava $E$-theory Mark Hovey Wesleyan University mhovey@wesleyan.edu In this paper, we revisit the calculations of the operations and co-operations in Morava E-theory. Recall that the co-operations are the continuous functions from a profinite group G that is a version of the Morava stabilizer group to E_*. The operations are the completed twisted group ring E_*[[G]]. These results have appeared in the literature before. The advantage of this paper is that it is self-contained, works out all the details that are usually skipped over, and uses a new approach, not directly dependent on Morava's Annals paper on comodules, that the author finds fairly simple and elegant. Most of all, though, the author wrote this paper because he was unable to understand the proofs in the literature. He hopes it will be useful for people in the same unhappy situation.