This course provides a comprehensive foundation in sampling theory and survey methodology. It covers fundamental concepts of probability and non-probability sampling, estimation techniques under various sampling designs, and evaluation of estimator properties such as bias, variance, and efficiency. The course emphasizes simple random, stratified, systematic, and unequal probability sampling methods, along with ratio, regression, and cluster sampling techniques. Students develop analytical skills to design surveys, select appropriate sampling strategies, and interpret results in real-world statistical investigations.