The concept of Aggregators is receiving large attention when new business cases for Smart grids are presented. Several studies propose different schemes of aggregating load and/or production. However, many of these studies are tailored for one specific market or network, making the generic value of the work small. The objective of the work presented in the paper is to analyze the fundamental needs for aggregating small scale loads or production units from a technical, financial and regulatory point of view. The final results of the analysis can work as a foundation for developing more elaborate aggregation business cases. These can later be analyzed from a technical and economical standpoint by, e.g., simulations.