Vol. 31 Num. 1 (2011) Richard Barwell Editorial2 David Tall Crystalline concepts in long-term mathematical invention and discovery ABSTRACT 3 Daniel Chazan , Patricio Herbst Challenges of particularity and generality in depicting and discussing teaching ABSTRACT 9 Susan Gerofsky Ancestral genres of mathematical graphs ABSTRACT 14 Moshe Renert Mathematics for life: sustainable mathematics education ABSTRACT 20 Christine Suurtamm Communication: Fractal images27 Reinhard Oldenburg Communication: Some thoughts on mathematics in the workplace and in school28 Tamsin Meaney Only two more sleeps until the school holidays: one child's home experiences of measurement ABSTRACT 31 Duncan Samson , Marc Schäfer Enactivism, figural apprehension and knowledge objectification: an exploration of figural pattern generalisation ABSTRACT 37 - Contributor affiliations and contact information44