A "technical book on macroevolution and the historical development of evolutionary theory.^[1] The book was twenty years in the making,^[2]published just two months before Gould's death.^[3] Aimed primarily at professionals,^[4] the volume is divided into two parts. The first is a historical study of classical evolutionary thought, drawing extensively upon primary documents; the second is a constructive critique of the modern evolutionary synthesis, and presents a case for an interpretation of biological evolution based largely on hierarchical selection, and the theory of punctuated equilibrium (developed by Niles Eldredge and Gould in 1972).^{[5]" (Wikipedia article on The Structure of Evolutionary Theory, accessed 03-2017).}