Database/website	Date and time	Search strategy	Number of hits
African Development Bank (AfDB): https://www.afdb.org/en/documents/publications/	17 August 2017	Search for all countries in 11 indexed sectors related to the environment	4
Asian Development Bank (ADB): https://www.adb.org/publications	17 August 2017	Four free text searches using filters for evaluation, publications, papers and reports.	52
ATAI Research: https://www.atai‐research.org/emerging‐insights/?	18 August 2017	Need to manually screen all hits	42
Centre for International Forestry Research (CIFOR): http://www.cifor.org/library/	18 August 2017	Two free text searches, one filter linked to publication type applied	31
DFID Research for Development (R4D): http://r4d.dfid.gov.uk/	18 August 2017	Four free text searches, one of which used a filter for topic	485
Inter‐American Development Bank Publications: https://publications.iadb.org/facet‐view?locale‐attribute=en&field=type_view	17 August 2017	Five free text searches using no filters	8
International Food Policy Research Institute Library (IFPRI): http://library.ifpri.info/discover/collections/	18 August 2017	Three free text searches, no filters applied	62
International Institute for Environment and Development (IIED): http://pubs.iied.org/about/	18 August 2017	Four free text searches, no filters available	385
United Nations Development Programme (UNDP): http://www.undp.org/content/undp/en/home/library.html	17 August 2017	Five free text searches using filters for three sectors	55
United National Environmental Programme: http://www.unep.org/publications/	17 August 2017	Four free text searches using no filters	19
World Bank Open Knowledge Repository: https://openknowledge.worldbank.org/	18 August 2017	Four free text searches, one of which used a filter for topic	589
International Fund for Agricultural Development (IFAD): https://www.ifad.org/pub/overview	28 August 2017	Go through publication series. From thematic series: agriculture, climate change, community driven development, nutrition. Also go through IFAD occasional papers and IFAD research series	86
Food and Agriculture Organisation of the United Nations (FAO): http://www.fao.org/publications/en/	31 August 2017	Go through the following publication series: climate change, climate smart agriculture, livestock and environment, REDD+	292
3ie Repository of Impact Evaluations: http://www.3ieimpact.org/en/evidence/impact‐evaluations/	28 August 2017	Environment filter, keyword: payment for ecosystem services, keywords: payment for environmental services	173
3ie RIDIE (Registry for International Development Impact Evaluations): http://ridie.3ieimpact.org/	28 August 2017	Environment filter, keyword: payment for ecosystem services, keywords: payment for environmental services	120
Innovations for Poverty Action (IPA): http://www.poverty‐action.org/projectevaluations	28 August 2017	Environment filter, keyword: payment for ecosystem services, keywords: payment for environmental services	11
J‐Poverty Action Lab: https://www.povertyactionlab.org/evaluations	28 August 2017	Environment and energy filter	39
Conservation Evidence: http://www.conservationevidence.com/	28 August 2017	Forest conservation filter, keyword: payment for environmental services, keyword: payment for ecosystem services	122
Climate Change Agriculture and Food Security (CCAFS) publications: https://ccafs.cgiar.org/publications	28 August 2017	Keyword: payment for environmental services, payment for ecosystem services	9
Conservation International publications: http://www.conservation.org/publications/Pages/default.aspx	28 August 2017	Go through all publications	90
IUCN Library: https://portals.iucn.org/library/dir/publications‐list	28 August 2017	keywords: community management, payment for environmental services, payment for ecosystem services, payment	12
Biodiversity International: http://www.bioversityinternational.org/e‐library/publications/	28 August 2017	keywords: community management, payment for environmental services, payment for ecosystem services, payment	16
GEF evaluation database: http://www.gefieo.org/evaluations/all?f[0]=field_ieo_grouping%3A312	31 August 2017	Go through all pubs (thematic and impact)	57
AgEcon: https://ageconsearch.umn.edu/?ln=en	15 September 2017	Keywords: payment for environmental services, payment for ecosystem services	110