Volume 1 of Quantitative Research Methods in Communication Science covers the foundational and general issues, operationalization and measurement, as well as study design anddata collection. The section on foundational issues includes chapters on the philosophy of science, causal inference, replicability and open science, statistical power, and ethical issues in quantitative research. The section on operation and measurement includes chapters on concept explication, scale development, establishment of scale unidimensionality, and reliability and validity assessment. The section on study design and data collection includes chapters on experimental studies, survey research, sampling, content and text analysis, the virtual reality method, online data collection, and the collection of digital data. This volume is the first of two that cover state-of-the-art quantitative communication research methods.