Matrices are very powerful for intersecting or cross-tabulating items in your database. This example looks at cross referencing interviews with a coding scheme to do an in-case-or cross case analysis but you can use matrices to cross references nodes with each other to check for co-occurrences or to consider nodes with demographic/profiling information from participants or even closed and open questions in a questionnaire. Matrices offer a strategic view of data that you could not get by say, reading through the contents of a node, because they reveal previously unseen patterns in your data.