This introductory lecture will review dynamic light scattering and zeta potential measurements. I will review sizing measurements by dynamic light scattering, introduce the utility of light scattering measurements, provide useful tips for analyzing DLS measurement results and provide example data from a variety of applications. An overview of zeta potential will also be discussed. Zeta potential is a function of both the particle surface and the dispersant and provides information about interfacial behavior important for formulated products. Another important application for zeta potential is during the clarification/treatment of drinking water.