“…It is known that this set of generators of M g is not minimal, and a great deal of attention has been paid to the problem of finding a minimal (or at least small) set of generators or a set of generators with some additional property. For different approaches to this problem see [3,5,7,8,10,11] and references there. The main purpose of this note is to prove that for g ≥ 1 the extended mapping class group M ± g is generated by three symmetries, i.e.…”