What is your intended usage for this?
Optical triggers are fine if the remote flash (and its Wein) are within line of sight and are not in an environment with other distracting light sources such as other people's flashes and/or direct sunlight.
If you have more robust needs, then think about radio triggers. There are very cheap ones available on eBay called "Gadget Infinity". If you want more reliability, then Elinchrom Skyports and Pocket Wizards you should research.