%0 Journal Article %T Enrichments over symmetric Picard categories %A V. Schmitt %J Mathematics %D 2008 %I arXiv %X Categorical rings were introduced by Jibladze and Pirashvili in their paper "Third Mac Lane cohomology via categorical rings", Journal of Homotopy and related structures, 2, 2007, 187-216. We call those "2-rings". In these notes we present basic definitions and results regarding 2-modules. This is work in progress. %U http://arxiv.org/abs/0812.0150v2