Considering the importance of official statistics in the country and also the course of official statistics in the syllabus of statistics students in universities and also the approval of official statistics major in the master's degree in the High Council of Educational Planning of the Ministry of Science, Research and Technology in 2017 and student admission in this field since 1397, the provision of course resources for this field is very important. The present book, as one of the textbooks in this field, has stated the concepts, principles, and theoretical foundations of the survey methods and tries to acquaint readers with the concepts related to survey methods by focusing on the sample survey. The main purpose of this book is acquaintance with survey methods (sample survey, census, and register-based statistics) with a focus on sampling including all the major steps and activities, that are done in a sample survey in terms of subject, sampling, implementation, data processing and extraction as well as monitoring. To this end, in this book, readers are introduced to sample survey designs including thematic design, sampling design, questionnaire design, implementation plan, monitoring plan, training plan, and data entry and processing plan, and pre-test before conducting the survey. Also, stages of a survey, are presented, including organizing, training, data collection (field operations), monitoring, data processing, and data extracting, including data entry activities, address editing, coding, editing and imputation, tabulation, and confidentialising information. This book also tries to acquaint readers with the principles and concepts of official statistics, statistical systems, methods of data collection, sources of statistical errors, including sampling and non-sampling errors, and methods of evaluating the quality of statistics. This book was written by Dr. Zahra Rezaei Ghahroudy, Dr. Roshanak Ali Akbari Saba, and Mr. Alireza Zahedian and was published in November 2018.