A convening on immunization delivery costs (October 14-15, 2015) supported by the Bill & Melinda Gates Foundation brought together approximately 40 experts and policy makers to review the current evidence on immunization delivery costs across a range of delivery strategies and platforms, vaccines and age groups. The main aim of the meeting was to collectively identify essential information needs, methodological issues, gaps in use of data for policy and at country level, as well as priorities and actions needed to support a common understanding of the direction of future efforts in this field. The specific objectives of the meeting were to (1) present the review a subset of current literature on published immunization delivery costs; (2) identify additional sources of delivery cost information; (3) assess the sources of data and general quality of delivery cost data; (4) discuss methodological issues that affect the quality of data; (5) identify the uses of delivery cost information for a range of stakeholders from countries, industry, donors, multilateral agencies and the GAVI Alliance and how well data and evidence are used; (6); identify key gaps in delivery costs, relative to stakeholder uses; and, (7) generate recommendations and conclusions, stemming from the evidence and discussions. In order to meet these objectives, participants were active in completing a pre-meeting survey, as well as invited to submit posters of current work on delivery cost (published or unpublished). A background working paper was also distributed to participants prior to the workshop. Appendices 1-3 provide the meeting participant list, the agenda and a summary of responses to key questions from the pre-meeting survey. Appendix 4 provides summary of small group work conducted during the convening meeting. A separate file Appendix 5 provides a copy of the 14 posters that were submitted.