This research is about the development of an integrated model of design that combines descriptions of design content and process in order to improve the design practitioner's ability to navigate complex projects. It seeks to support the future work of design practitioners and educators by providing them with a framework to contextualise and understand it, which is germane to their practice and requisite to contend with increasing levels of complexity found within emerging technical, social, cultural, environmental and political design contexts. The approach is phenomenological, based on a longitudinal study using a hybrid methodology including a theoretical review of existing models of the design process and reflective design practice studies with quantitative and qualitative assessments of practice outcomes. The result is to adopt the navigational analogy used by previous researchers. To advance the view that content-based models are perceived as more useful to designers than models that describe the process of designing. The conclusion combines both types of model to produce an integrated conceptual framework that enables designers to map out levels of decision-making against process activities, providing ability to plot progress within a project and exercise a management overview. The process-based element assists planning and forecasting and the content-based element assists navigation and review.