This project was sponsored by Defense Advance Research Projects Agency (DoD) ARPA Order No. 3803, monitored by Naval Electronic System Command under Contractor No. N00034-R-0251. It was also sponsored by Defense Advance Research Projects Agency (DoD) ARPA Order No. 4871, monitored by Naval Electronic Systems Command under Contract No. N00039-84- C-0089.

This book focuses on object-oriented concurrent computing, which can be considered a model of concurrent programming, and proposes a new programming language, ConcurrentSmalltalk, which is based on object-oriented concurrent computing. The book also shows the efficiency of object-oriented concurrent computing through the design, implementation, and evaluation of ConcurrentSmalltalk. ConcurrentSmalltalk is designed to be upwardly compatible with Smalltalk-80. In the book, the ConcurrentSmalltalk object model is first proposed. Next, issues which arise from maintaining compatibility with Smalltalk-80 are discussed. Finally, the ConcurrentSmalltalk virtual machine which executes the ConcurrentSmalltalk programs is proposed.