In many developing countries, maternal mortality rates remain high with huge poor-rich inequalities. Programmes aimed at improving maternal health and preventing maternal mortality often fail to reach poor women. Vouchers potentially are an effective financial mechanism for targeting health services to the poor. We examine voucher and Health Equity Fund (HEF) schemes for safe delivery in three health districts in Cambodia and draw lessons learned for further improvement and scaling up. Data on voucher and HEF schemes were collected from reports and routine health information system combined with the personal observations of the authors and those from nine focus group discussions. We found that voucher and HEF schemes increased deliveries in public health facilities. Voucher and HEF beneficiaries accounted for about one third of total facility deliveries and these increased sharply over time without decreasing the number of self-paying deliveries. But, the impact of both schemes on improved access to safe delivery for poor pregnant women remains limited. We outline several limitations of the voucher schemes. Finally, we conclude that vouchers plus HEFs, if well designed and implemented, have a strong potential to address financial barriers to improved access for poor pregnant women to safe delivery. Yet, they do not overcome many non-financial barriers. To be fully effective, vouchers and HEF should be implemented together with supply-side interventions. More evidence is needed before further scaling up.