Linking VB and C

What is the best way to link C and VB. I know that it can be done using the command shell. But I face some problem with that. My problem is that until the exe file is excuted i cannot proceed to the next statement in vb code. I want make sure that before the next statement is executed (in the VB code) the exe file is completely run. I did it by putting a loop between the statements but again this depends on the system speed and load. It can fail sometimes.Please suggest me a solution to this.