I changed my ignition switch and now my car won't start

Check over all your fuses. What happens when you turn the key? Any clicking noise? Have you checked power at the starter? Alex

Why did you change it and what was it doing before you changed it? I assume you changed the key cylinder and not the *ignition switch*(electrical part). did you have the key cylinder in the run position before removing the old one,and installed the new one in the same position?