As the economic cycle in the US matures, investors’ focus is sharpening on when and at what level official US interest rates will peak. A key part of the debate centers on equilibrium real interest rates, the theoretical rate at which capital supply and demand in the economy are in perfect balance and which effectively determines whether monetary policy is restrictive or loose. In this issue of Investment Insights we assess current estimates of the real equilibrium rate in the US relative to the Fed’s own long term estimates—and consider the likelihood that the Fed may over tighten in this cycle.