BACKGROUND: To track donor assistance to maternal, newborn, and child health-related activities is necessary to assess progress towards Millennium Development Goals 4 and 5 and to foster donor accountability. Our aim was to analyse aid flows to maternal, newborn, and child health for 2005 and 2006 and trends between 2003 and 2006. METHODS: We analysed and coded the complete aid activities database for 2005 and 2006 with methods that we developed previously to track official development assistance. For the 68 Countdown priority countries, we report two indicators for use in monitoring donor disbursements: official development assistance to child health per child and official development assistance to maternal and neonatal health per livebirth. FINDINGS: Donor disbursements increased from US$2119 million in 2003 to $3482 million in 2006; funding for child health increased by 63% and that for maternal and newborn health increased by 66%. In the 68 priority countries, child-related disbursements increased from a mean of $4 per child in 2003 to $7 per child in 2006; disbursements for maternal and neonatal health increased from $7 per livebirth in 2003 to $12 per livebirth in 2006. Nonetheless, disbursements fell in some countries. After adjustment for other determinants, countries with higher under-5 mortality received more official development assistance per child, but official development assistance to maternal and newborn health did not seem to be well targeted towards countries with the greatest maternal health needs. INTERPRETATION: Donor resource tracking should be continued to help hold donors accountable and encourage targeting of resources to countries with greatest needs.