The ST4S vendor guide is updated twice per year. All ST4S assessments are performed against a version of the ST4S assessment framework. The assessment framework is versioned as follows:
<year>.<period>
For example, ‘2021.1’ indicates the version of the guide that would apply for assessments covered from January to June 2021. ‘2021.2’ indicates the version of the guide that would apply for assessments from July to December 2021.
The current version of the guide can be found below: