WPA has been hackable for quite a while with free tools. Wireless is not secure.
802.X with EAP/TLS. Adjust WAP and client signal strength to controlled physical space as much as possible. Limit unauthorized physical access. Classify data into security categories and never use wireless or Internet access on machines handling the more sensitive categories.
Security is an ongoing game.
Assume that all these methods will be broken eventually. Keep evolving!