According to the Federal Communications Commission, 2.4 billion automated marketing calls are made every month, the equivalent of the more than seven for every American. These computerized marketing calls, or “robocalls,” are the most common source of complaints to the FCC.

These are not just inconvenient and annoying calls made by legitimate companies engaging in aggressive marketing. In fact, many robocalls are made by criminals looking to manipulate, lie, and steal from those on the other side of the line.

The Better Business Bureau, a nonprofit consumer advocacy group, has for some time tracked the evolution of practices and scams perpetrated by robocallers. The BBB and other groups have a number of suggestions — most of which are quite simple — for ways to handle and avoid these calls.

Click here to see nine ways to deal with robocalls.

Some of the solutions to robocalls are extremely simple. Not sharing your number with businesses unless absolutely necessary is one solution, and simply ignoring unknown or unlisted numbers is another.

The Federal Trade Commision established on June 27, 2003 the National Do Not Call Registry. Calling or going online and registering one’s phone number makes it illegal for businesses to make unsolicited calls to that number. As of the end of last year, there were more than 220 million American phone numbers registered.

While some are tempted to get revenge on telemarketers by giving misinformation or dragging the call out, these strategies accomplish very little, particularly in the case of robocalls. According to the BBB, speaking on the phone to a robocaller or pressing buttons can indicate that there is a person who picks up calls attached to your number, potentially increasing the volume of future calls.

These are the nine best ways of dealing with robocalls.