In an environment of declining survey response rates, decreased use of landline telephones, and rising costs of telephone and in-person surveys, political science researchers have increasingly turned to online surveys to measure public opinion. In light of the growing prevalence of online surveys in peer-reviewed journals, it is important to recognize the wide variation in their design and quality. In the most literal sense, an online survey simply refers to a particular mode of interviewing in which the respondent self-completes a questionnaire over the Internet, whether on a computer, tablet, or cell phone. However, conducting surveys online is far more complex than simply relocating an in-person or phone survey onto the Internet. Online surveys use a variety of different sampling designs, recruitment strategies, and implementation procedures, all of which have implications for data quality. The considerable heterogeneity in online surveys is too often overlooked. Given the discipline’s overall embrace of the method, making sense of this heterogeneity is essential to understanding how best to design and analyze online surveys and, ultimately, evaluate knowledge claims being made with the resulting data. Fortunately, research on online surveys constitutes a large and growing segment of the survey methodology literature. The purpose of this bibliography is to provide a resource for understanding the variation in methods and quality of online data collection, the relative advantages and disadvantages of using online surveys, and best practices for designing and analyzing online surveys.