Promotion and study of knowledge sharing among philanthropic foundations globally, led by western institutions and scholars, pays minimal attention to knowledge sharing undertaken by national and local foundations in non-western regions and countries. Yet such settings are often sites of extensive international (largely western-led), philanthropic investment, where interfoundation knowledge sharing may be especially valuable. This article reports research on knowledge sharing in 12 nationally based foundations, working locally in youth development in Jordan and Palestine (West Bank). Findings from case studies and interview data reveal a range of internal knowledge-sharing activities, linked to individual foundations’ program development and incorporating beneficiary perspectives. These developments contrast significantly with the lack of external knowledge sharing and the absence of invitations to share knowledge with international foundations, active in these countries. The implications of these findings for foundation philanthropy theory and practice, and for knowledge-sharing scholarship are considered and a continuing research agenda proposed.