The European Central Bank has published Occasional Paper No 392, a research synthesis from the ChaMP network on how production networks and heterogeneity across firms, sectors and countries affect monetary policy transmission. The paper, which carries a disclaimer that it does not necessarily reflect the views of the ECB, finds that input-output linkages across the economy materially change how shocks propagate: supply shocks tend to be amplified and become more persistent, while demand shocks, including monetary policy shocks, are generally dampened. It also concludes that large shocks can produce nonlinear effects, including a steeper Phillips curve, and that production networks weaken the usual alignment between inflation and output dynamics, creating clearer trade-offs for policy. The paper highlights that a sector’s position in the network can matter more than its size, with upstream and central sectors exerting disproportionate influence when disrupted. Research reviewed in the paper shows that downstream sectors closer to final demand tend to react faster to monetary policy shocks, while upstream sectors respond more slowly but often more persistently, and that financial frictions can either reinforce or offset disinflation depending on where they sit in the network. It also stresses that cross-border input linkages and imported inputs can materially amplify inflation pass-through, and that firm-level business-to-business transaction data reveal concentration and heterogeneity that sector-level models can miss. For policy analysis, the paper argues for greater use of granular indicators such as sector centrality, frequency of price changes and exposure to upstream cost pressures to distinguish supply-driven from demand-driven inflation and calibrate state-contingent responses. It also notes that services inflation and other underlying measures may provide a better signal of domestic inflation pressure than headline inflation when goods prices are being driven by networked supply shocks.