In 2013 the WHO Regional Office for Europe developed the Guide to tailoring immunization programmes (TIP), offering countries a process through which to diagnose barriers and motivators to vaccination in susceptible groups and design tailored interventions. To take stock of TIP implementation so far, an external committee of six leading global experts conducted an evaluation in June to December 2016, informed by country assessments, a review of national and regional documents and an online regional survey. The evaluation committee concluded that national immunization managers in the Region were generally aware that TIP exists (although its focus and intentions were not well understood by all), and that there was strong demand for the type of research it addresses. A number of countries were planning TIP activities in the short or long term and requesting WHO support and guidance. It was clear that the TIP process has a number of important strengths and has had a programmatic impact in all the countries where it has been applied. The evaluation found the most commonly cited strengths of the TIP approach to be community engagement and qualitative research, enhancing the ability of programmes to “listen” and learn, to gain an understanding of community and individual perspectives. Other strengths cited were its ability to facilitate the questioning of assumptions, generate localized insights and identify interventions responsive to the insights and relationships established through the approach. The interdisciplinary stakeholder engagement, the insights gained and the relationships generated merely by assembling a diverse group of stakeholders added value in themselves. Similarly, the initial step of collectively agreeing on the susceptible groups was cited as a valuable accomplishment in its own right. In this way, TIP seems to be particularly relevant for approaching groups with common environmental, social or behavioural characteristics. The emphasis on considering changes to service delivery rather than focusing solely on communication was another highlighted strength of the approach. Some countries that have implemented the TIP approach have evaluated the results and found that the interventions were seen as positive. One country has been able to show an increase in vaccination uptake (Lithuania); the others have not yet measured the bottom-line health impact of their TIP-related interventions. WHO engagement and support were highly appreciated by country implementers, but these entail the risk of dependence and reduced local ownership and leadership. A critical aspect of TIP implementation is the fact that changing service delivery is a long, slow and often complicated process. Emphasizing that the purpose of TIP should go beyond identification of susceptible groups and diagnosis of challenges to the development of appropriate and effective interventions, the evaluation committee recommends that WHO should place emphasis on helping countries translate diagnostics into interventions and start the necessary process of overall change. The implementation of interventions should be supported by an emphasis on 4 enhanced local ownership; integrated diagnostic and intervention design; and follow-up meetings, advocacy and potentially incentives like seed funding for intervention and evaluation activities. The time requirements and investment of human and financial resources documented in the evaluated countries are other aspects that need to be addressed. Suggestions for this included shortening the diagnostic exercise and developing a basic needs assessment tool for countries to complete as a first TIP step. The committee recommends that future TIP materials should be more user-friendly, shorter and simpler than the current guide, drawing on user feedback and user-centred design research. The stepwise structure and WHO branding should be retained, along with the illustrations and figures that have supported national planning. It also recommends that WHO should continue to offer training workshops and take additional steps to establish a community of practice with TIP-implementing countries.