Back Translation is a process in which a document is translated from the source language into a foreign language, and then back into the source language by two independent translators.
The first translator translates the original document into the foreign language, the second translator translates from the foreign language back into the source language. At the end of this process, there are three documents: two documents in the source language, which can be compared to make sure that the translation is accurate, and a third document which is in the requested foreign language.
The Back Translation method is the most common method in Israel.
 Advantages –
1.    Minimizing errors– the document is translated by two professional translators, an objective professional reviews the document.
2.    Accuracy – translation into a foreign language and back into the source language reveals sources of inaccuracy and double meaning, thus the translator has the option of correcting the translation and providing an accurate translated document.
3.    Quality – at the end of the day, the quality of the translation is the most important thing. The document is reviewed by two independent translators, promising a qualitative and professional translation.
4.    Maintaining the meaning– the original document's author has all three documents, and can verify that the translation is accurate and answers his needs.
5.    Cost – even though the process involves more than one translator and the result obtained is more accurate and professional, employing the back translation method is identical in cost to the Double Validation method.
 
Double Validationis a duplicate validity examination of a document in order to make sure that it has been translated correctly and that it is faithful to the origin. In the validation process, three factors are involved: 1. The translator; 2. First validator who examines the translation and corrects it; 3. Second validator who reviews the translated document, which already includes the changes and corrections made by the first validator, in comparison to the original document. 
At the end of the process, there are two documents: the source document, and the translated document, with corrections and changes made by two additional translators who have performed the validation process of the translation.
Advantages–
1.    Quality– the document is reviewed by translators who are proficient in the specific field.
2.    Faithful to the original– the examining eye is a professional one, to make sure no details have been omitted during the translation.
3.    Time– relatively shorter timelines in comparison with to Back Translation.
 
From the translators' point of view, there is not difference between the methods. In both methods, the translators' work focuses on two documents: the source document and the translated document. The choice between the two methods is done by the customer only.
 
The translation work, accuracy, professionalism, thoroughness, attention to details, and most of all – love of the written word, these are the things that make the difference between one translated document to another.