1 ITSMS (ISO 20000) Information Technology Services Management System ITSMS is an important scheme based on the ISO standard for the services of IT. ITSMS is work as a business promoter, defining the service level, and quality of the IT services, & also focusing on the different keys required by the stander. OSS is a leading company that provides the Lead AuditorTraining course for those interested candidates who makes their career in Quality. This course is certified by Exemplar Global (RABQSA) & recognized by the QCI, and NABCB,.