While strain energy is often invoked to rationalize observed reactivity patterns, and is commonly cited as the cause of the heightened reactivity of small carbo-and heterocyclic rings, and cycloalkynes, it is evident that thermodynamic strain-release arguments alone are insufficient to explain the origins of such reactivity. Through analysis of radical and nucleophilic additions to small rings, and azide/cycloalkyne click reactions, bond delocalization is shown to be an equally important factor that works alongside -and in many cases dominates -strain release effects to promote these facile reactions. To aid the integration of these ideas into novel 'strain release' strategies, a simple model has been developed that offers rapid and quantitative reactivity predictions.