2011: Sir Charles Antony Richard Hoare, FRS, FREng, FBCS

Citation

"Tony Hoare's long career in computing is studded with seminal engineering and scientific contributions to Programming Languages; his views on programming language design have been recognized as profound even by those who declined to follow his advice.

Two contributions stand out as fundamental: the development of what is now known as Hoare logic, and Communicating Sequential Processes. Hoare logic is a system for reasoning about imperative programs. It was introduced in the 1969 article "An Axiomatic Basic for Computer Programming", which is perhaps the most influential 6-page paper ever published in CACM. Drawing on earlier work of Robert Floyd, an entire sub-area of computer science has developed from Hoare's initial ideas; many modern verification systems build on Hoare logic.

Only 9 years later, CACM published Hoare's paper on Communicating Sequential Processes (CSP). Contemporary with Milner's CCS, but pursuing complementary goals, CSP has been enormously influential. It provided the basis for the occam programming language and its realization in the Transputer; it has been used for modeling and verifying the concurrency properties of critical software systems; and it inspired a flowering of subsequent concurrency research.

Although either of these contributions would alone justify the achievement award, Hoare is doing more with his Unifying Theories research, which aims to unify theories of programming across paradigm, abstraction level and semantic style. Beyond all of this, Tony is renowned for his unfailing courtesy, his inspiration, and his dedication to his chosen calling. He is the epitome of a scholar and a gentleman."