I'm working on an application (a data analysis system built in C++) for which it would be helpful to have nested (multidimensional) containers other than ordinary arrays. I have defined a generic 'data' class which I like to store in std::vector's. For a very simple example, a 'data' might be a double representing a student's score on an exam, or in more complex settings it might be some sort of spatial map, or a multidimensional set of records for a medical patient. I am interested in structures where 'data' is nested across multiple levels. For example, test scores are nested within students, students nested within teachers, nested within school districts, etc. For a single layer of nesting a std::map > seems to be an ideal way to store such data, largely because text strings can be used to identify subjects: dat["johnny"] // returns a std::vector of pointers to johnny's test scores. This is often the way that data are stored in files to be analyzed. I'm looking for some sort of C++ container that is more convenient for multiply nested data than std::map > > ... >, but which will allow me to write expressions like: dat["LAUSD"]["Central High"]["Ms. Jones' Class"]["Johnny"] // same vector as above. Can something like the Boost multi-array package be extended to handle this?