QUALITY-ASSURED PRODUCTS & SERVICES ISO 9001 Thesaurus is committed to maintaining and exceeding its ISO 9001-accredited service. You can rest assured that you are in safe hands, as our business operates to the highest, externally audited, quality standards. Information technology infrastructure library (ITIL) ITIL is a best-practice framework for supplying high-quality IT services. It forms the backbone of our approach to providing extremely high standards of service delivery. Employee ITIL accreditation is an essential part of ensuring that we consistently adhere to these principles. PRINCE2 Thesaurus aligns with PRINCE2 ‘Projects in Controlled Environments’ methodology and maintains employee accreditation in this key management discipline.