| 1978 | Title of Professor of mathematical sciences, The State Council of Poland |
| 1973 | D.Sc. in Mathematical Sciences (Habilitation, or post-doctoral Thesis), ``Algebraic Theory of Programs", Institute of Mathematics of PAS |
| 1965 | Ph.D. in Mathematics (Doctoral Thesis), ``On recognition of words of formal languages", Institute of Mathematics of PAS |
| 1955 | M.Sc. in Mathematics, ``Topological properties of solutions of differential equations'', Warsaw University |
| 1984 - now:     | Local computations, distributed algorithms |
| 1976 - now : | Concurrency theory, foundations of concurrent processes, concurrent algorithms |
| 1968 - 1976: | Semantics of programs, formal models of programs and computational processes, mathematical foundations of computer science |
| 1964 - 1967: | Theory of programs, formal language theory |
| 1955 - 1963: | Programming, programming languages, compiler design |
| 1993 - 1999:    | Jagiellonian University, seminar on distributed algorithms |
| 1993 - 1997: | Jagiellonian University (Cracow), professor, lectures on concurrency |
| 1990 - 2000: | Seminar on Math. Foundations of Computer Science, ICS PAS (with P. Dembinski, W. Penczek, A. Tarlecki, J. Winkowski) |
| 1989 - 1990: | Seminar on Concurrency, Warsaw University (with L.Czaja and J.Winkowski) |
| 1986 - 1987: | Seminar on Concurrency, Dept. of Computer Science, Leiden University |
| 1986 - 1987: | Course on Concurrency II, Dept. of Computer Science, Leiden University |
| 1975: | Course on Mathematical Theory of Programs for post - graduated students, Technical University of Warsaw |
| 1975 - 1988: | Seminar on Mathematical Foundations of Computer Science at ICS of PAS (with A.Blikle and J.Winkowski) |
| 1974: | Course on Algebraic Theory of Programs at International Banach Centre of Mathematics |
| 1972 - 1973: | Courses on Mathematical Semantics of Programs for post -- graduated students, Technical University of Warsaw |
| 1972 - 1973: | Courses on Formal Language Theory for post -- graduated students, Warsaw University, Dept. of Mathematics |
| 1971 - 1973: | Courses on the Theory of Algorithms, Seminar on Automata Theory, Warsaw University, Dept. of Mathematics |
| 1971 - 1974: | Seminar on Mathematical Foundations of Computer Sciences at Institute of Computer Sciences of PAS |
| 1970 - 1971: | Introduction to Computer Science, course at Dept. of Mathematics of Warsaw University |
| 1968 - 1970: | Courses on Computability Theory at Warsaw University, Dept. of Mathematics |
| 1964 - 1968: | Courses on programming languages at Institute of Mathematics of PAS |
|     | Aachen Univ. (D) | 1979,1984, 1986 |
| | Aarhus Univ. (DK) | 1975, 1977,1986 |
| | Amsterdam Math.Centrum (NL)     | 1976, 1986 |
| | Arco Felice CNR Lab. (I) | 1975 |
| | Berlin, Humboldt Univ. (D) | 1972 |
| | Bonn GMD (D) | 1979, 1981, 1983, 1984, 1986, 1989 |
| | Bordeaux Univ. (F) | 1990, 1992, 1994, 1997, 2005 |
| | Bucharest Univ. (R) | 1964 |
| | Budapest, Acad. of Sci. (H) | 1968 |
| | Eindhoven Techn. Univ. (NL) | 1987 |
| | Hamburg Univ. (D) | 1979,1984 |
| | Helsinki Univ. (SF) | 1984 |
| | Leiden Univ. (NL) | 1984,1987,1989,1996 |
| | Novisibirsk Acad. of Sci. (SU) | 1972 |
| | Oldenburg Univ. (D) | 1989 |
| | Oslo Techn. Univ. (N) | 1977 |
| | Paris Univ. Paris VIII, XI (F) | 1972,1973,1978,1990,1992,1993,1995 |
| | Pisa Univ. and CNR (I) | 1975,1978 |
| | Princeton Univ. (USA) | 1996 |
| | Rocquencourt INRIA (F) | 1972,1973 |
| | Salerno Univ. (I) | 1975 |
| | Tampere Univ. (SF) | 1978 |
| | Turku Univ (SF) | 1978 |
| | Utrecht Univ. (NL) | 1978 |