This document identifies the key considerations for measurement systems when realized in virtual form@ and provides recommendations in terms of design and features to provide a degree of mitigation for the issues identified. This Recommendation takes the premise that the measurement functions are virtualized along with network functions@ because access to the virtualized infrastructure can be both more difficult and more resource intensive for physical measurement systems (which do not need a new set of recommendations). The implementation of metrics@ models@ and their methods of measurement is usually beyond the scope of SG12 Recommendations@ except for Implementer??s guides. Therefore@ considerations developed in this work must emphasise how the metrics@ models@ and their methods would change or be augmented in the case where their implementation is virtual. Further@ new methods to characterize the deployment environment and adapt the measurements to better suit the current circumstances are desirable. There are five study areas for the design and development of Virtual Measurement Systems (VMS) within the scope of this Recommendation: 1. On-demand Deployment (packaging@ preferred form of virtualization@ positioning@ measurement system connectivity@ role of Software Defined Network (SDN) techniques). 2. Accuracy in Deployment (isolation of the measurement function@ mitigation of breaches@ trade-offs between accuracy and resource demands@ timestamp accuracy considerations). 3. New opportunities for Deployment (in continuous integration/continuous deployment@ or CI/CD verification testing). 4. Virtual Networking in Deployment (networking needs of measurement systems). 5. Security (in collaboration with SG17 and IETF). All 5 of the major study areas have been included in this version.