@elfring said in Support for multi-index containers?: Would you like to distinguish any more between the usage of one- and two-dimensional structures for data models? Nope, the 2 dimensional structure is strictly more general of the 1D version so anything that goes for the first works in the second case. beginRant(); You have been discussing a lot of theoretical problems relating to models across different threads. In all of them the feeling has been that you are uselessly overcomplicating things. I feel it would be useful for you and easier for us to walk you through a concrete example of what you are trying to achieve rather than discuss endlessly on theoretical concepts. endRant();