It is described how the measurement of n gamma -coincidences can be used to
identify single-particle states in Sn-133. This method, in combination wit
h the improved yields at ISOLDE, has facilitated firm determination of thre
e excited single-particle states in Sn-133: p(3/2), h(9/2) and f(5/2) The i
(13/2) State is not observed in this experiment and probably unbound, and t
he data did not allow a firm identification of the p(1/2) state. The result
s are well reproduced in a Woods-Saxon calculation based on the data from t
he Pb-208 region and taking into account the distance from beta -stability
of the Sn-132 region.