I have over 20 years engineering experience within the defence and aerospace sectors. My company Sigma-Systems Ltd can provide the following services on an ad hoc and temporary basis. Documentation reviews and revision update independent checking. Management of system and sub-system requirement evidence. Verification strategy analysis ensuring correct verification evidence. Authorship of system design and evidence documentation. Requirement management. Design and documentation change implementation. Coherence across project platforms. Management of verification evidence databases. Review of verification evidence.