Tailoring three-point functions and integrability

We use integrability techniques to compute structure constants in N = 4 SYM to leading order at weak coupling and to leading order in the planar expansion. Three closed spin chains, which represent the single trace gauge-invariant operators in N = 4 SYM, are cut into six open chains which are then sewed back together into some nice pants, the threepoint function. The algebraic and coordinate Bethe ansatz tools necessary for this task are reviewed. Our results hold for scalar single trace operators of arbitrary size. Finally, we discuss the classical limit of our results, anticipating some predictions for quasi-classical string correlators in terms of algebraic curves.