Before COVID-19, most surveys in low- and middle-income countries used face-to-face interviewing. Researchers have quickly pivoted to using mobile phone surveys due to COVID-19, using a mix of live interviews, interactive voice response (IVR), and short message service (SMS, or text messaging). In low- and middle-income countries, mobile phone surveys are still relatively new, emerging only in the past decade. As a result, researchers are still developing methodological best practices to address challenges with coverage, response, and measurement. This webinar will describe mobile phone surveys in low- and middle-income countries, including modes, sampling, training, operations, response rates, representativeness, measurement, and weighting. For each topic, we will review emerging best practices, operational approaches, and recent literature. Throughout the webinar, we will discuss examples of successful mobile phone surveys on COVID-19 and other topics.