When you read about as many examples of scams and identity theft as I do, you start to notice patterns. Even though the details may change, most scams are based on one of a few tried-and-true structures.

This actually makes it easier for you to avoid them, however. Instead of learning the minutiae of every new con job that comes down the pike, you can apply a few basic principles to steer clear.

One of those principles is similar to “Who Initiated Contact,” which I wrote about several months ago. This time the question is, “Did you take action that would lead to this transaction?” Here are a few examples.

Lottery Scams

Lottery scams always seem to come up, but people still fall for them, so a little refresher never hurts.

With a normal, legitimate lottery, you begin the transaction by purchasing a lottery ticket. You then wait for the numbers to be called. If you win one of the big prizes, you take action again by contacting the lottery office, presenting the ticket, filling out paperwork. If you don’t take this action, they might know when and where a winning ticket was sold, but they won’t contact you.

Lottery scams don’t start with action on your part. Out of nowhere, someone emails you and informs you of a lottery you’ve won. It’s the exact opposite of how a genuine lottery works. The rest of the scam runs in similar bizarro-fashion, with the victim sending money, but if you stop to think, “Did I take action that would logically lead to this?” first, you won’t even bother to get that far.

Employment Scams

Employment scams come in all shapes and sizes, and their objectives range from taking your money outright to leaving you as the only traceable, domestic link in a money laundering scheme.

However, most of the time, when you find a new job it’s because you took some action first. You filled out an application, sent a resume, networked with people in the industry. You probably didn’t just wait for a job to fall on your head.

Employment scams often don’t wait for you to take action. You’ll get an email that claims you’ll make hundreds of dollars per day. You’ll be “hired” without an interview or application. Pay is often wildly out of proportion for the work you’ll supposedly be performing ($10 to stuff an envelope, for example), which is another way to apply the question of whether you took action; would any employer in their right mind pay you over a hundred dollars for less than an hour’s worth of mindless work?

There is a caveat here, though: not all employment scams can be weeded out this way. If you’re actively looking for a job and posting resumes on job websites, you’re taking action that could lead to employment opportunities (post a resume on Monster.com and see how many work-at-home “payment processor” jobs (i.e. money laundering) you’ll be offered via email, sometimes within an hour). To further complicate matters, fraudulent companies often post fake listings on job sites, so you might be tricked into sending your resume to them first. Always research any company before you apply, but also remember that high-paying job offers don’t just fall out of the sky.

Mortgage Settlement Scams

A scam recently surfaced in Virginia that targets homeowners who are underwater or in foreclosure. It starts with a phone call that tells victims they are owed money from a federal mortgage settlement and ends with the victims revealing bank account numbers in hopes of receiving a check, only to be remotely cleaned out by crooks.

The scam is based somewhat on fact—there was a settlement with mortgage lenders meant to make good on bad foreclosure practices—but those eligible still have to take action first. Applications and other paperwork have to be filed, and the homeowners have to be the ones who start the process.

Asking “Did I take action that would lead to this?” isn’t the only method to spot a scam, and as noted above, it’s not always the best test, but it’s a good weapon to keep in your arsenal for the next time a possible scam shows up on your radar.