He returned in 1978 as ma*tre de conf*rences to the University of Paris VII, where in 1981 he became professor extraordinarius (professeur de premi*re classe) and in 1991 professor ordinarius (professeur en classe exceptionelle). In 2012 he became professor emeritus. At the beginning of _his_ career Chenciner worked on differential topology and its applications to dynamical systems, following the pioneering efforts of Stephen Smale, and also worked on singularity theory. <sep>, Pronoun: his <sep>, A: Chenciner <sep>, B: Stephen Smale