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Name:  Dr Stephen Castell FIMA MInstP MBCS MCMI CPhys MIoD CITP MEWI

Job Title:  Chairman

Organisation:  CASTELL Consulting

Number of years in current position:  40 years.  See:

Qualifications:  BSc in Mathematics, Physics and Psychology, MSc in Mathematics, Computer Science and Fluid Mechanics, PhD in Mathematics

Briefly describe the organisation you work for: 

Management and Financial Consultants in Information Technology.  Professional ICT Experts and Consultants.

Explain what you do on an average day at work: 

One area of my work involves being an ‘Expert Witness’ in complex disputes over failed IT systems.  When a software developer agrees to build an IT system, then the end result should be ‘fit for purpose’ – which is not always the case.  If the client is unhappy with the product, it can lead to legal action, particularly as these IT systems cost huge amounts of money. As an Expert Witness I help to give evidence on whether the software really is fit for purpose.

This type of work involves carefully reading thousands of evidence documents and also includes our own expert-designed testing of the software and systems.  I also use mathematical models such as the Constructive Cost Model (COCOMO) which assesses the value of the software development costs.

When not working on client projects, my work is centred on marketing and promotion, plus ‘Continual Professional Development’: writing-up journal papers and online articles for publication, running and participating in Seminars and Conferences, or attending Meetings such as the British Computer Society’s Law Specialist Group.

What do you like most about your job?  Above all, being my ‘own boss’.

 What stimulated your interest in maths, and when?  I was a ‘late developer’; and I only just scraped through my A Levels in Mathematics and Physics.  It was not until university that I discovered an appetite, and gift, for Mathematics, and suddenly I couldn’t get enough of it.

My love of Music also rapidly developed at this time, which is no coincidence as there is a strong connection between maths and music.  I am a performed composer, under my nom de plume Leo King.

 What influenced your career choice?  I achieved a First Class Honours BSc Degree, in Mathematics, Physics and Psychology, University of London.  I went on to the University of Nottingham where I achieved an MSc in Applied Mathematics (Computer Science and Fluid Mechanics), and then a prize-winning PhD in Mathematics, Certain Transformations in Gas- and Magnetogas-Dynamics.

 I then ‘naturally’ went first into industrial research, where I was able to apply my skills in mathematical modelling to solve practical engineering research problems.  I then moved on to Management Consultancy in commercial computer systems and software.

Which skills do you consider to be essential for your job?  I must be creative, analytical, practical and professional.  I have to be excellent at speaking and writing, and I need to be a good negotiator and leader.  As an Expert Witness I need to be authoritative, which comes from being able to put together a well worked-through analysis which is based on the evidence.