Every nonempty closed
subset of a dendrite can be the fixed point set of a self-map, but in general it
cannot be the fixed point set of a map with special properties. Necessary
conditions found here for the fixed point sets of homeomorphisms and monotone
surjections of dendrites are mainly concerned with the order of the possible
fixed points, and extend earlier results by G. E. Schweigert and L. E. Ward,
Jr.