In this half-day tutorial we will describe a new tool that has emerged in the last 5 years for conducting online behavioral research: crowdsourcing platforms. The term crowdsourcing has its origin in an article by Howe (2006), who defined it as a job outsourced to an undefined group of people in the form of an open call. One of the main benefits of these platforms to behavioral researchers is that they provide access to a large set of people who are willing to do tasks—including participating in research studies—for relatively low pay. The crowdsourcing site with one of the largest subject pools is Amazon’s Mechanical Turk (AMT), so it is the focus of this tutorial.