IntroductionDespite the unparalleled success of immunisation in the control of vaccine preventable diseases, immunisation coverage in South Africa remains suboptimal. While many evidence-based interventions have successfully improved vaccination coverage in other countries, they are not necessarily appropriate to the immunisation needs, barriers and facilitators of South Africa. The aim of this research is to investigate barriers and facilitators to optimal vaccination uptake, and develop contextualised strategies and implementation plans to increase childhood and adolescent vaccination coverage in South Africa.MethodsThe study will employ a mixed-methods research design. It will be conducted over three iterative phases and use the Adopt, Contextualise or Adapt (ACA) model as an overarching conceptual framework. Phase 1 will identify, and develop a sampling frame of, immunisation stakeholders involved in the design, planning and implementation of childhood and human papillomavirus immunisation programmes in South Africa. Phase 2 will identify the main barriers and facilitators to, and solutions for, increasing vaccination coverage. This phase will comprise exploratory qualitative research with stakeholders and a review of existing systematic reviews on interventions for improving vaccination coverage. Using the findings from Phase 2 and the ACA model, Phase 3 will develop a set of proposed interventions and implementation action plans for improving immunisation coverage in South Africa. These plans will be discussed, revised and finalised through a series of participatory stakeholder workshops and an online questionnaire, conducted as part of Phase 3.EthicsEthical approval was obtained from the South African Medical Research Council (EC018-11/2018). No risks to participants are expected. Various steps will be taken to ensure the anonymity and confidentiality of participants.DisseminationThe study findings will be shared at stakeholder workshops, the website of Cochrane South Africa and academic publications and conferences.