This four page document provides an overview of the systematic review entitled: Effectiveness of interventions to reduce carbon-emissions within secondary healthcare. The summary provides links to the full report and accompanying evidence and gap map. These links are also provided at the bottom of this page. This work is carried out by Exeter Policy Research Programme Evidence Review Facility [NIHR 200695]. Views expressed are those of the authors and not necessarily those of the NHS, NIHR, Greener NHS team or NHS England. This is the second version of this document. Amendments from the first version include correction of the link to the Evidence Gap Map and Final report.