I have an array with a structure like {{a,b},{{c,d},{e,f}}} . It appears to save and import, but when the imported array is examined in FullForm, it is incorrectly structured.  Thus the original array in FullForm looks like List[List[a,b],List[List[c,d],List[e,f]]]  but the imported looks like this in FullForm List["a,b","{{c,d},{e.f}}"]  The indexing to individual elements is incorrect.  Thus MatrixForm[xi[[2,1]]] gives the error message Part::partd: "Part specification \!\({\"{a, b}\", \"{{c, d}, {e, f}}\"}[[2, 1]]\) is longer than depth of object."  I have tried several formats such as Table, List with Export and Import and have also tried Save and Get. It seems that there should be a way to Export or Save in FullForm, but I cannot find it.