This paper argues that microeconomic shocks can lead to significant aggregate fluctuations in an economy with intersectoral input-output linkages. The authors show that as the economy becomes more disaggregated, the rate at which aggregate volatility decays is determined by the structure of the network capturing these linkages. They characterize this relationship in terms of the importance of different sectors as suppliers to their immediate customers and as indirect suppliers to downstream sectors. This higher-order interconnection captures the possibility of "cascade effects" where productivity shocks to a sector propagate not only to its immediate downstream customers but also indirectly to the rest of the economy. The results highlight that sizable aggregate volatility is obtained from sectoral shocks only if there is significant asymmetry in the roles sectors play as suppliers to others, and that the sparseness of the input-output matrix is unrelated to the nature of aggregate fluctuations. The paper provides a general mathematical framework for analyzing such propagations and characterizes how the extent of propagations of microeconomic shocks and their role in aggregate fluctuations depend on the structure of interactions between different sectors.This paper argues that microeconomic shocks can lead to significant aggregate fluctuations in an economy with intersectoral input-output linkages. The authors show that as the economy becomes more disaggregated, the rate at which aggregate volatility decays is determined by the structure of the network capturing these linkages. They characterize this relationship in terms of the importance of different sectors as suppliers to their immediate customers and as indirect suppliers to downstream sectors. This higher-order interconnection captures the possibility of "cascade effects" where productivity shocks to a sector propagate not only to its immediate downstream customers but also indirectly to the rest of the economy. The results highlight that sizable aggregate volatility is obtained from sectoral shocks only if there is significant asymmetry in the roles sectors play as suppliers to others, and that the sparseness of the input-output matrix is unrelated to the nature of aggregate fluctuations. The paper provides a general mathematical framework for analyzing such propagations and characterizes how the extent of propagations of microeconomic shocks and their role in aggregate fluctuations depend on the structure of interactions between different sectors.