I want to pass 2-D arrays from VB to dll's written in C and want to manipulate those arrays inside the dll (i.e. carry out mathematical operations on the individual elements of those arrays) and return 2-D array from dll to VB. The elements of the array are either double or float. Any full length example(code on the VB as well as the c/c++ end) of a way to tackle this problem will be highly appreciated.