Having problems with connecting to Minecraft Multiplayer Server

A friend and I keep getting an issue with Multiplayer Mode and every time I would attempt to log into his server it would say:

Failed to connect to the server
Connection timed out: connect

I know I put in the information exactly correct and still get the issue, I'm not sure what could be the cause of it or what could even fix it. It has been happening every time I try to join the server my friend has up and so I felt maybe to report it.