  This paper reviews recent advances in the study or circumstellar masers and
masers found toward supernova remnants. The review is organized by science
focus area, including the astrophysics of extended stellar atmospheres, stellar
mass-loss processes and outflows, late-type evolved stellar evolution, stellar
maser excitation and chemistry, and the use of stellar masers as independent
distance estimators. Masers toward supernova remnants are covered separately.
Recent advances and open future questions in this field are explored.
