| Excalibur | 1988 | Spain | |||
| &-Prolog | 1990 | String and List Processing | Horn clause | Spain | |
| ACE | 1994 | Experimental and other | Spain | Parallel logic language | |
| CIAO | 1994 | Experimental and other | Horn clause | Spain | Distributed And/Or parallel prolog |
| &ACE | 1995 | Spain | |||
| PROLIX | 2000 | Spain | |||
| O'Ciao | 2002 | Spain |