Emmanuel Letier

Associate Professor
Software Systems Engineering Group
Department of Computer Science
University College of London

Email: e.letier@ucl.ac.uk
Office: UCL Engineering Front Building, Room 3.01

Overview

I am an Associate Professor of Software Engineering in the Department of Computer Science at UCL. My teaching and research focus on requirements engineering and software architecture, with an emphasis on modelling and formal reasoning techniques. Before moving into computer science, I studied applied mathematics and philosophy.

Requirements Engineering Book

I am writing a book on Requirements Engineering. The draft is a work in progress and can be accessed through the link above. The book is based on my lectures at UCL, and I am happy to share teaching materials upon request. Feedback and encouragement are also highly appreciated.

Research

My research focuses on software requirements and architecture, particularly how to discover, analyse, and communicate the requirements and architectures of complex software systems.

A central theme of my work is that understanding stakeholder goals is fundamental to building the right software—software that fulfils its intended purposes and delights its users. This is especially important in AI-based systems, where ensuring alignment with stakeholder goals is a key concern.

Stakeholder goals can be analysed using a combination of natural language (both human reasoning and computational processing), formal logic, and mathematical models. The logical and mathematical formalisms extend our natural communication and reasoning capabilities by enabling powerful tools for model checking, model synthesis, multi-objective optimisation, and Bayesian statistical analysis.

Analysing stakeholder goals also requires reasoning about trade-offs between conflicting objectives, anticipating obstacles to goal satisfaction, and managing uncertainty about how design choices affect those goals. Uncertainty plays a key role not only in requirements engineering but also in strategic release planning, software testing and debugging, software evolution, and the management of technical debt.

The aim of my research is to develop sound and practical techniques for the iterative generation, testing, debugging, and optimisation of software requirements, architectures, and code. Ultimately, these techniques seek to support the development of software systems that are more dependable, secure, usable, maintainable, and beneficial to all stakeholders.

Selected publications

On uncertainty in strategic release planning

O. Oni, E. Letier, Analysing Uncertainty in Release Planning: A Method and Experiment for Fixed-Date Release Cycles, ACM Transactions on Software Engineering and Methodology (TOSEM), Vol. 31, Issue 2, April 2022.

On analysing uncertainty in goal models

S. A. Busari, E. Letier, RADAR: A Lightweight Tool for Requirements and Architecture Decision Analysis, ICSE, 2017.
E. Letier, D. Stefan, E. T. Barr, Uncertainty, Risk, and Information Value in Software Requirements and Architecture, ICSE, 2014.

On analysing obstacles to goal satisfaction

E. Letier, A. van Lamsweerde. Obstacle Analysis in Requirements Engineering: Retrospective and Emerging Challenges. IEEE Transactions on Software Engineering, 2025.
A. van Lamsweerde and E. Letier, Handling Obstacles in Goal-Oriented Requirements Engineering, IEEE TSE, 2000.

On managing requirements conflicts

A. van Lamsweerde, R. Darimont, E. Letier, Managing Conflicts in Goal-Driven Requirements Engineering, IEEE TSE 1998.

On deriving software requirements from stakeholder goals and domain assumptions

E. Letier and W. Heaven, Requirements Modelling by Synthesis of Deontic Input-Output Automata, ICSE, 2013.
E. Letier and A. van Lamsweerde, Agent-Based Tactics for Goal-Oriented Requirements Elaboration, ICSE, 2002.

On inferring requirements from scenarios

E. Letier, Jeff Kramer, Jeff Magee and Sebastian Uchitel, Monitoring and Control in Scenario-Based Requirements Analysis, ICSE, 2005.

Teaching

I teach a course on software requirements and architecture to MSc students at UCL and supervise students projects in collaboration with industry.

I am writing an online book based on my requirements engineering lectures. You can read the current draft of the book here: Requirements Engineering.

Short bio

I joined UCL as a lecturer in 2006. I hold a PhD in Software Engineering from the University of Louvain in Belgium. Prior to my doctoral studies, I obtained an engineering degree in Applied Mathematics and a bachelor degree in Philosophy from the same university.

I served as Program Co-Chair of the International Requirements Engineering Conference in 2016. I am regularly involved in program committees for various conferences, notably for the International Requirements Engineering Conference (RE) and the International Conference in Software Engineering (ICSE). I chaired the BCS Requirements Engineering Specialist Group from 2011 to 2017 and served as head of UCL Software Systems Engineering research group from 2017 to 2020.

Publications

Also on: Google Scholar, DBLP

E. Letier, A. van Lamsweerde. Obstacle Analysis in Requirements Engineering: Retrospective and Emerging Challenges. IEEE Transactions on Software Engineering, 2025.
J. Dąbrowski, E. Letier, A. Perini, A. Susi. Mining User Feedback For Software Engineering: Use Cases and Reference Architecture. IEEE International Requirements Engineering Conference (RE'22), Melbourne, Australia, 2022.
J. Dąbrowski, E. Letier, A. Perini, A. Susi. Analysing app reviews for software engineering: a systematic literature review. Empir Software Eng 27, 43 (2022).
O. Oni, E. Letier, Analysing Uncertainty in Release Planning: A Method and Experiment for Fixed-Date Release Cycles, ACM Transactions on Software Engineering and Methodology (TOSEM), Vol. 31, Issue 2, April 2022.
J. Dąbrowski, E. Letier, A. Perini, A. Susi. Mining user opinions to support requirement engineering: an empirical study. CAiSE 2020, pp. 401-416, 2020.
S. A. Busari, E. Letier, RADAR: A Lightweight Tool for Requirements and Architecture Decision Analysis, Proc. 39th International Conference on Software Engineering 2017 (ICSE 2017). [RADAR Download and Examples]
O. Oni, E. Letier, Optimizing the Incremental Delivery of Software Features Under Uncertainty. REFSQ 2016: 36-41
E. Letier, D. Stefan, E. T. Barr, Uncertainty, Risk, and Information Value in Software Requirements and Architecture, Proc. 36th International Conference on Software Engineering 2014 (ICSE 2014).
D. Stefan and E. Letier, Supporting Sustainability Decisions in Large Organisations, Proc. ICT4S. 2014.
E. Letier and W. Heaven, Requirements Modelling by Synthesis of Deontic Input-Output Automata, Proc. 35th International Conference on Software Engineering 2013 (ICSE 2013). [Download the prototype tool and examples]
L. Duboc, E. Letier and D. S. Rosenblum, Systematic Elaboration of Scalability Requirements through Goal-Obstacle Analysis, IEEE Transactions on Software Engineering, Jan 2013.
Mario Cortes Cornax, Alexandru Matei, Emmanuel Letier, Sophie Dupuy-Chessa, Dominique Rieu, Intentional Fragments : Bridging the Gap Between Organizational and Intentional Levels in Business Processes, 20th International Conference on Cooperative Information Systems, CoopIS 2012, Roma, Italy, Sept 2012.
C. Fitzgerald, E. Letier and A. Finkelstein, Early Failure Prediction in Feature Request Management Systems: an Extended Study, Requirements Engineering Journal, Special Issue: RE’11 Best Papers, 2012.
C. Fitzgerald, E. Letier and A. Finkelstein, Early Failure Prediction in Feature Request Management Systems, Proceedings RE 2011 – 19th IEEE International Requirements Engineering Conference, Trento, Italy, September 2011. (Distinguished Paper Award)
W. Heaven and E. Letier, Simulating and Optimising Design Decisions in Quantitative Goal Models, Proceedings RE 2011 – 19th IEEE International Requirements Engineering Conference, Trento, Italy, September 2011. [Matlab simulation and optimisation files for the paper's example (an ambulance system)]
V. Veerappa and E. Letier, Understanding Clusters of Optimal Solutions in Multi-Objective Decision Problems, Proceedings RE 2011 – 19th IEEE International Requirements Engineering Conference, Trento, Italy, September 2011.
D. Stefan, E. Letier, M. Barrett, M. Stella-Sawicki, Goal-Oriented System Modelling for Managing Environmental Sustainability, 3rd International Workshop on Software Research and Climate Change, Lancaster, United Kingdom, August 2011.
V. Veerappa and E. Letier, Clustering Stakeholders for Requirements Decision Making, Proceedings REFSQ 2011 – 17th International Working Conference on Requirements Engineering: Foundation for Software Quality, Essen, Germany, March 2011.
Sawyer, P., Bencomo, N., Whittle, J., Letier, E., Finkelstein, A., Requirements-Aware Systems A research agenda for RE for self-adaptive systems, Proceedings RE 2010 – 18th IEEE International Conference on Requirements Engineering, Sydney, Australia, September 2010.
Bencomo, N., Whittle, J., Sawyer, P., Finkelstein, A., Letier, E., Requirements Reflection: Requirements as Runtime Entities, Proc. 32nd International Conference on Software Engineering 2010 (ICSE 2010) New Ideas and Emerging Results (NIER) track, Cape Town, South Africa, 2010
Duboc,L., Letier,E., Rosenblum,D.S., Wicks,T. (2008). A Case Study in Eliciting Scalability Requirements. Proc. of the 16th International Requirements Engineering Conference, IEEE Computer Society Press.
Egyed, A., Letier, E., Finkelstein, A. (2008). Generating and Evaluating Choices for Fixing Inconsistencies in UML Design Models. 23rd IEEE/ACM International Conference on Automated Software Engineering (ASE 2008).
Letier,E., Kramer,J., Magee,J., Uchitel,S. (2008). Deriving event-based transition systems from goal-oriented requirements models. Automated Software Engineering 15(2), 175-206. [Download: zip file with all models]
E. Letier, Jeff Kramer, Jeff Magee and Sebastian Uchitel, Fluent Temporal Logic for Discrete-Time Event-Based Models, Proceedings ESEC/FSE 2005 – 5th joint meeting of the the European Software Engineering Conference and the ACM SIGSOFT Symposium on the Foundations of Software Engineering, ACM Press, Lisbon, Portugal, September 2005.
E. Letier, Jeff Kramer, Jeff Magee and Sebastian Uchitel, Monitoring and Control in Scenario-Based Requirements Analysis, Proceedings ICSE 2005 – 27th International Conference on Software Engineering, ACM Press, St. Louis, Missouri, USA, May 2005.
E. Letier and A. van Lamsweerde, Reasoning about Partial Goal Satisfaction for Requirements and Design Engineering, Proceedings FSE 2004 – 12th International Symposium on the Foundation of Software Engineering, ACM Press, Newport Beach, CA, November 2004, pp. 53-62. (Best Paper Award)
A. van Lamsweerde and E. Letier, From Object Orientation to Goal Orientation: A Paradigm Shift for Requirements Engineering, in Radical Innovations of Software and Systems Engineering in the Future, M. Wirswing (ed.), Springer-Verlag, LNCS 2941, 2004, pp. 325-340.
R. De Landtsheer, E. Letier and A. van Lamsweerde, Deriving Tabular Event-Based Specifications from Goal-Oriented Requirements Models, Requirements Engineering Journal, Vol. 9, n° 2, Springer-Verlag, May 2004, pp. 104-120. (Revised and expended version of RE’03 paper)
R. De Landtsheer, E. Letier and A. van Lamsweerde, Deriving Tabular Event-Based Specifications from Goal-Oriented Requirements Models, Proc. RE’03 – International Conference on Requirements Engineering, IEEE Press, Montery, California, September 2003, pp. 200-211. (Best Research Paper Award – A revised and expended version appeared in Requirements Engineering Journal)
E. Letier and A. van Lamsweerde, Deriving Operational Software Specifications from System Goals, Proceedings FSE 2002 – 10th International Symposium on the Foundation of Software Engineering, ACM Press, Charleston, November 2002, pp. 200-211.
E. Letier and A. van Lamsweerde, High Assurance Requires Goal Orientation, Proceedings RHAS ’02 – International Workshop on Requirements for High Assurance Systems, Essen, September 2002.
E. Letier and A. van Lamsweerde, Agent-Based Tactics for Goal-Oriented Requirements Elaboration, Proceedings ICSE 2002 – 24th International Conference on Software Engineering, ACM Press, Orlando, May 2002, pp. 83-93.
E. Letier, Reasoning about Agents in Goal-Oriented Requirements Engineering, Phd Thesis, Université Catholique de Louvain, Dépt. Ingénierie Informatique, Louvain-la-Neuve, Belgium, May 2001.
A. van Lamsweerde and E. Letier, Handling Obstacles in Goal-Oriented Requirements Engineering, IEEE Transactions on Software Engineering, Special Issue on Exception Handling, Vol 26, n° 10, October 2000, pp. 978-1005.
A. van Lamsweerde, R. Darimont, E. Letier, Managing Conflicts in Goal-Driven Requirements Engineering, IEEE Transactions on Software Engineering, Special Issue on Managing Inconsistency in Software Development, Vol 24, n° 11, November 1998, pp. 908-926.
A. van Lamsweerde, E. Letier, Integrating Obstacles in Goal-Driven Requirements Engineering, Proceedings ICSE’98 – 20th International Conference on Software Engineering, ACM Press, Kyoto, April 98, pp. 53-62.