Strategic activity is often punctuated through the application of strategy tools. Despite widespread use, a lack of understanding exists regarding the impact such tools and their practices have on an organization's strategy process. Of the growing body of research tackling the phenomenon, none appears to extend beyond an intra-organizational setting. Acknowledging the importance of multi-organizational partnerships, particularly in the public sector, in this paper an attempt is made to help fill this void through examining the application and effect of a scenario planning process at an inter-organizational level. Conceptualizing scenario planning as a practice of simplexity, where complexity of thought combines with simplicity of action, an in-depth, longitudinal case study is used to demonstrate the importance and interaction of sensemaking, storytelling and organizing in creating meaning within strategizing activities at the inter-organizational level. However, also demonstrated is the relative weakness of the output of the scenario planning process - the stories - as a boundary object capable of transferring knowledge and meaning to the intra-organizational level. Through empirical and theoretical integration a model is developed presenting the flow of practices and artefacts used in sensemaking within inter- and intra-organizational strategizing.