A water soluble package comprises a polymeric film, the polymeric film comprising a polymeric backbone derived from a polymer which is water soluble, as defined herein, and one or more derivatising groups attached to the backbone, the derivatising group(s) being derived from a material having a ClogP of from 0.5 to 6 and/or being derived from a parent material comprising a C4 to C22 hydrocarbyl chain.