'Survey before plan' was the working principle of the Scottish biologist and town planner Patrick Geddes, set out in his 1915 book Cities in Evolution: a place should be studied systematically, its geography, economy, history and social life, before any intervention is designed. Geddes ran civic exhibitions and an Outlook Tower in Edinburgh as instruments for reading the city and its region as a whole. He argued planning should work with the grain of place rather than impose abstract schemes.
It established the idea that planning must be evidence-based and rooted in regional and social analysis rather than drawing-board geometry. This survey-and-diagnosis method became a foundation of professional town and regional planning.