Aggregation articles in various areas of economics, statistics, and accounting are surveyed to develop a common body of fundamental queries which underlie these articles. The conditions for total consistency between a microsystem and a macrosystem that have been developed for various systems are investigated and are related to the consistency conditions for general relational systems. This is followed by an analysis of other types of queries commonly observed in the aggregation literature, e.g., partial consistency, errors and biases, evaluation and selection of aggregation functions. Finally, an assessment is made of the significance of aggregation theory in scientific investigations.