The ATHENA project is funded by the European Commission under the topic of the Science with and for Society work programme SwafS-09-2018-2019-2020 ‘Supporting research organisations to implement gender equality plans’. ATHENA overall aims at supporting the development and implementation of Gender Equality Plans (GEPs) in 6 research performing organisations (RPOs) and 2 research funding organisations (RFOs) in Europe. To that purpose, Work Package (WP) 4 (named ‘GEPs development and implementation’) includes a specific task (T4.3) titled ‘Drafting a Toolbox for preparation of customized GEPs’, whose aim is to provide key tools, resources and recommendations to develop the GEPs. This deliverable is the result of this task, entitled ‘ATHENA Toolkit for transforming the institutional culture in terms of gender aspects’. The tools, resources and recommendations included herein are distributed into 8 thematic areas, which are presented in sections 2.2 and 3.