This manual provides a basic review of practical procedures for computing sampling errors and gives guidelines on how to analyse and utilize sampling errors. It underscores the importance of including detailed information in survey reports on the sampling variability of survey estimates. Many illustrations are presented in the manual for the benefit of sampling practitioners. Chapter 1. Introduction -- Part 1. Computation -- Chapter 2. Computing sampling errors: comparison among primary selection -- Chapter 3. Computing sampling errors: comparison among sample replications -- Chapter 4. Computing sampling errors in practice -- Part 2. Analysis -- Chapter 5. Decomposition of the total variance -- Chapter 6. Data reduction and modelling -- Chapter 7. Presentation and use of information on sampling errors.