As corporate spies proliferate, it is true that many companies are vulnerable to eavesdropping. Which is why eavesdropping is increasingly necessary. But before to prevent eavesdropping, you need to find out, you will be what means eavesdropping. The vast majority of eavesdropping is done through mobile phones. So in general, you just need to buy a cell phone jammer. If it's for radio bugs, you may also need the ability to jam WiFi.