The effective deployment of the bureaucracy is fundamental to government performance and economic development. We study the organizational architecture of the central administration for a large sample of municipal governments in Colombia. Our analysis yields four main findings. First, municipal population is the strongest predictor of the size of the local bureaucracy, but there is substantial variation in bureaucratic size even among municipalities with similar population or expenditure on public personnel. Second, while almost all municipal governments have employees at all hierarchical levels, the share of top managers monotonically decreases and the shares corresponding to lower layers grow as bureaucracies expand. However, only the largest bureaucracies achieve a pyramidal structure. Third, average wages monotonically increase with the hierarchical level, but they remain largely constant within levels for bureaucracies of different sizes. Fourth, larger shares of higher-level bureaucrats are robustly associated with municipal tax revenue per capita, conditional on bureaucratic size