in work in the mid-90's, john stembridge noted that several combinatorial statistic generating functions carried enumerative information when the variable was set to $-1$. he dubbed this the "$q=-1$ phenomenon. in joint work with vic reiner and dennis stanton, we have noted that stembridge's phenomenon generalizes to when $q$ is an appropriate root of unity. we called this the "cyclic sieving phenomenon." i will describe several instances of this phenomenon and some open problems.