The framework described in this manual is based upon the lessons learnt by the Mobilise-D consortium during the state-of-the-art Technical Validation Study (TVS) (Mazzà et al., 2021). The primary objective of the TVS was to explore the validity of a single wearable device attached to the lower back and the selected algorithms to estimate a select list of digital mobility outcomes in laboratory and real-world settings in different patient populations. A device agnostic approach ensured that a method was developed that was generalisable to any device with the required technicalrequirements and attachment modalities. To date, this is the largest and most harmonised technical validation study on mobility and represents the efforts of a large group of multi-disciplinary experts from more than 30 academic, technical, and pharmaceutical industry organisations throughout the globe. This manual draws from the experiences and lessons learnt of the state-of-the-art validation procedure to provide a comprehensive overview of the most valid methods of data capture, optimal approaches to technical validation and specific real-world scenarios where digital mobility outcomes can be quantified with the highest accuracy and precision. The aim of this Technical Implementation Manual is to provide a guidance reference to encourage the wide-spread and consistent adoption of proven methods required for the valid measurement of DMOs across a range of health conditions and a much-needed harmonisation of best practice.