This paper describes Tempo++, a concurrent programming language which combines logic programming and object-oriented programming. Tempo++ improves on traditional concurrent logic programming languages (e.g. Parlog, KL1) and their object-oriented extensions (e.g. Polka) by explicitly specifying the safety properties of programs. The language provides a framework in which algorithms for a variety of paradigms can be expressed, derived and compared. In the language, concurrency issues are separated from the code, minimizing dependency between application functionality and concurrency control. It is, in general, possible to test different synchronisation schemes without modifying the code of the operations, and conversely, a synchronisation scheme may be reused by several applications. The main features of the language are illustrated by the implementation of a classical concurrent problem.