Scenario planning is a strategy tool with growing popularity in both academia and practical situations. Current practices of scenario planning are largely based on existing literature which utilises scenario planning to develop strategies for the future, primarily considering the assessment of perceived macro-external environmental uncertainties. However there is a body of literature hitherto ignored by scenario planning researchers, which suggests that Perceived Environmental Uncertainty (PEU) influences the microexternal as well as the internal environment of the organisation. This paper reviews the most dominant theories on scenario planning process and PEU, developing three propositions for the practice of scenario planning process. Furthermore, it shows how these propositions can be integrated in the scenario planning process in order to improve the development of strategy.