[3] Born in London in 1963, Lethbridge grew up in Denmead and attended St John's College in Portsmouth[4] until he immigrated with his family to Canada in 1975.

[5] He received his BSc in 1985 and his MSc in 1987 in Computer Science from the University of New Brunswick.

In 1994, he received his PhD in Computer Science and Artificial Intelligence from the University of Ottawa under supervision of Douglas Skuce for a thesis about tools for knowledge management,[6] entitled "Practical Techniques for Organizing and Measuring Knowledge.

"[1] In 1983, still studying, he started working as programmer and analyst for the Government of New Brunswick, where he assisted in the development of software for statistics, health insurance programs, and management information applications.

At the university he also taught courses in Fortran programming and Interactive Computing.