Sirius’ staff have supported some of the largest projects in UK Government, delivering successful Economic and Financial Cases for approval by HMT, following the guidance set out in the Treasury Green Book. We have applied cost-benefit analysis and cost-effectiveness analysis to select preferred options and deliver compelling Value for Money (VfM) arguments for future investment. We have delivered support to capital, infrastructure and service projects, using our expertise in OR/OA and Whole Life Cost analysis to increase confidence in financial estimates and manage the risks associated with very large investment projects. In UK Defence we have wide experience of delivering specialist products such as Concepts of Analysis (CoAs) and Operational Analysis Supporting Papers (OASPs). Critically, our expertise allows us to understand and work with senior stakeholders and deliver practical solutions for complex projects which often have socio-economic and strategic impacts.


Sirius has extensive OR/OA experience applied throughout the capability lifecycle from early stage concept development to acquisition in all domains. This has included applying soft methods and stakeholder engagement skills to structure problems, conducting historical trends and data analysis to identify trends and support concept development, and simulation modelling and Multi-Criteria Decision Analysis (MCDA) to evaluate options. Much of this analysis has been used to support capability acquisitions including requirements trade-off analysis, operational effectiveness / Analysis of Alternatives (AoA) studies and business case support, including benefits analysis. Our expertise and experience enables us to design and implement analysis and decision support techniques tailored to the client’s specific needs.


Sirius has a significant capability undertaking cost and risk related studies. Staff have developed whole life cost models and generated estimates for air, land, sea, space and joint systems, platforms and infrastructure for the UK MoD, NATO, other defence organisations and industry. These whole life cost estimates have been used to support Investment Appraisals, Combined Operational Effectiveness and Investment Appraisals and successful Business Cases. We are currently undertaking costing studies on C2 systems, on autonomous systems and a wide range of maritime assets.


Sirius specialises in the provision of Suitably Qualified and Experienced Personnel (SQEP) to deliver Systems Engineering Services to government and industry, using its core skills in Systems Engineering, Operational Research (OR), and Cost and Risk analysis. By drawing on best practice methods and techniques in each of these domains the individuals are able to develop innovative methodologies with the necessary quality and rigour to support the early analysis and definition of Systems Engineering tasks, projects and programmes.

Our experience in the nuclear, defence, space, security and transport sectors of the UK and NATO enables our team to provide a tailorable and scalable solution to support a diverse stakeholder group and community of varying sizes and complexity. Sirius can provide systems engineering support for your product, service or enterprise level systems. We can also provide you with a tailored solution for systems engineering within a managed life cycle and offer a collaborative approach, working with other engineering, analysis and management disciplines and specialisms.

Our capabilities cover the full lifecycle from Requirements Engineering; Architecture Development; Systems Analysis, Analysis of Alternatives; Integration Verification Validation and Testing; through to Sustainment; Disposal and Replacement.

With staff that are active members of INCOSE, we can provide you with technical leaders and a trusted service that is based on best practice and places systems thinking and systems approaches at the heart of any project.