Objectives: ePRO and IVRS PRO instruments are increasingly used in clinical trials.  As a result translations of such instruments are also increasingly required. Whilst the approach recommended in the ISPOR translation task force paper (Wild et. al 2005) should still be used, ePRO and IVRS instruments present some unique challenges during their translation and linguistic validation. This study seeks to clarify what some of those challenges are, and how to meet them. Methodology: Oxford Outcomes translation and linguistic validation projects involving ePRO/IVRS were reviewed to produce a list of tips on how best to localise such instruments. Results: Give translators information about limited screen size up front to avoid shortening strings later in the process. Participants in IVRS studies have to listen to the PRO instrument; therefore prompts should not be too long and have too many concepts (this helps both translators and participants). Avoid concatenation (where a sentence is split in the software coding and put back together at run time). Don’t split question stems from the questions. Provide translators with existing translations leveraged from previous translation projects to ensure consistency. Ideally cognitive debriefing of the translation should be carried out via the medium of final delivery (e.g. if it is on a handheld computer, the participants see the instrument on a handheld computer). It is worth having a linguist check final translated software/listen to recorded prompts - to ensure no errors have been introduced at software building / recording stage. Conclusion: With some forward planning, the challenges of translating and validating an ePRO or IVRS instrument can be met, ensuring a translation that is conceptually equivalent and suitable for use in the target country with the target patient population.