When indirect sampling is used jointly with the sampling of clusters of persons many complications arise for the survey statistician. One of the complications relates to the computation of the estimates from the survey. The production of estimates of simple totals or means can then become nightmares for the survey statistician. This book proposes a simple, easy to implement solution to this problem: the generalized weight share method. It presents the theory surrounding indirect sampling and the generalized weight share method as well as the different possible applications that drive its interest. The reader will find in this book the answer to questions that come, inevitably, when working in a context of indirect sampling.