Health promotion has a strong tradition of using planning models based on an a priori set of goals and processes defined by professionals. Those rational models only partly fit with today's view and practice of health promotion, where programmes can be considered as processes because they are guided by principles such as community participation and intersectoral collaboration. The aim of this paper is to provide a comprehensive view on approaches to planning in health promotion practice. To investigate these, Whittington's typology has been used. Whittington identifies four approaches to planning, i.e. classical, evolutionary, processual and systemic. In a retrospective multiple case study, we describe actual planning processes used in the development and implementation of a healthy ageing programme in three Dutch municipalities. These processes were described using data gathered by: interviews, participant observation and document analysis, and external auditing. Characteristics of the four planning approaches were used to interpret the data. The results show that, in practice, all forms of planning approaches were used, depending on the degree of complexity and dynamics of the context, the phase of the health promotion programme, and the time available. Our findings suggest that in the emergent practice of health promotion different approaches to planning are used. To make those planning approaches explicit and manageable for practice and science, discussion and reflection between stakeholders are essential.