INTRODUCTION: The increasing number of Quality of Life (QoL) assessments in multi-national clinical trials emphasizes the need for cross-culturally valid instruments to pool data across countries. The Urinary Incontinence QoL Questionnaire is a 28-item questionnaire developed in French and designed for use in women with urinary incontinence and investigates 5 domains and overall QoL. Prior to use in an international trial, the original questionnaire underwent linguistic validation in 6 countries. METHODS: The rigorous methodology involved recruiting a QoL specialist in each country to supervise the linguistic validation process. For practical reasons, a UK English version was produced prior to the other translations as a translation basis along side the French original. The following methodology was employed: two forward translations by two native target language speakers; backtranslation into French; comprehension test in a sample target population and international harmonization. The remaining languages followed the same process basing themselves both on the French and UK texts during forward and backward translations. RESULTS: Linguistic issues emerged, among which the translation of idiomatic French expressions such as "feeling well in one's skin" or "discouraged" for which descriptive equivalents had to be found in most languages to retain the original concept. Conceptual issues arose where the French original could be interpreted in more than one way. Close collaboration with the author was necessary to correctly interpret the original concepts and orient translations towards the correct interpretation. CONCLUSION: A rigorous methodology ensured conceptual equivalence and acceptability of the translations. Psychometric testing will be conducted to ensure reliability and validity of each translation, appropriateness of the questionnaire in each country, and comparability of data across countries.