Sampling is essential for making valid generalizations from data, and this chapter builds a thorough understanding of sampling theory and practice. The chapter covers population definitions, various sampling techniques, and their implications for inference. Probability sampling methods, including simple random sampling, stratified sampling, and cluster sampling, are compared with non-probability approaches such as convenience and snowball sampling. The importance of representativeness and bias is emphasized, particularly in business research where decisions often depend on customer or market samples. Concepts such as sampling distributions and standard errors are mathematically defined. Special attention is given to unequal probability sampling and its correction through weighting. The chapter concludes with strategies for balanced sampling and techniques for determining appropriate sample sizes for given levels of power and confidence.